Raman images showing the presence of three different molecules. (Courtesy: Max Planck Institute for Quantum Optics)
Frequency combs have been used by physicists in Germany and France to improve the performance of Raman spectroscopy – allowing the technique to identify several different molecules at the same time. The researchers say that it could be used to speed up the microscopic mapping of chemical species in a sample or be used to follow chemical reactions in real time. However, the new analytical method must be improved before it can be used routinely in the lab.
In coherent anti-stokes Raman spectroscopy, a sample is irradiated repeatedly by pairs of ultrashort laser pulses. The first pulse sets chemical bonds in the molecules vibrating, which causes the refractive index of the sample to vary periodically. This change in refractive index modulates the frequency of the second pulse. The gap between the two pulses is increased slightly with each subsequent pair, so the second pulse sees a slightly later point in the bonds’ vibration periods and its frequency is shifted by a slightly different amount. By looking at the sinusoidal variation in frequency shift with time lag, scientists can work out the vibration frequencies of the chemical bonds. As each type of molecule has a distinct signature of vibration frequencies, Raman spectroscopy can identify the presence of specific molecules in a sample.
Time consuming
The pair of pulses is usually generated from a single laser pulse that is split into two. One pulse is sent on a longer path, causing it to hit the sample slightly later. Changing the path length of that pulse varies the time lag. This works well if the aim of the measurement is to detect the presence of a known molecule. However, if there are several different target molecules – or if the goal is to identify unknown molecules – the entire measurement process must be repeated at multiple frequencies and this can be time consuming. The technique becomes more unwieldy if it is used to create a 2D image by scanning the light across a sample and acquiring Raman spectra at each pixel.
Now, researchers at the Max Planck Institute for Quantum Optics and Ludwig Maximilians University (LMU) and colleagues at University Paris-Sud have used frequency combs to get around this problem. Frequency combs produce an extremely rapid and stable series of femtosecond laser pulses, each containing a broad and highly regular spectrum of frequencies. Theodor Hänsch – the leader of the LMU and Max Planck groups – shared the 2005 Nobel Prize for Physics for inventing the frequency comb.
A thousand times faster
The team used two frequency combs, the second pulsing at a slightly slower rate than the first. As a result the combs moved in and out of phase, generating a series of pairs of pulses with a time gap that changes slowly. Because the technique does not involve the mechanical adjustment of a path length, it can acquire a single Raman spectrum about 1000 times faster than the traditional method. Furthermore, as each pulse contained a broad spectrum of frequencies, they could excite multiple bond vibrations simultaneously. Mathematical analysis of the complex relationship between the refractive index and the time lag between the pulses told the researchers what sinusoidal frequencies the pattern contained, and thus what chemical bonds – and therefore chemical species – had given rise to it.
There is a catch, however. The bond vibrations die out in picoseconds, so once the gap between the pulses has grown longer than this, the second pulse does not see any variation in refractive index at all until the time gap returns again to smaller values. “One of the limitations of our technique at the moment,” says team member Nathalie Picqué, “is that we can measure one full spectrum covering the entire fingerprint region [the electromagnetic region in which the bond vibrations occur] very quickly, but the time from one spectrum to the next is rather long.” The researchers plan to reduce this by using frequency combs that pulse more rapidly. Indeed, combs producing up to a billion pulses per second are available now and even faster combs are being developed.
Elegant combination
“Most of the elements here were done before,” says Yaron Silberberg of the Ultrafast Optics Group at the Weizmann Institute of Science in Israel. “People have used short pulses for Raman microscopy, and also people have used frequency combs for doing all kinds of tricks, but the combination is very elegant. They’ve combined two things and made you think, ‘Hey, how come nobody did this before?'”
Picqué hopes that the research will have applications beyond microscopy. “You could, for example, imagine that you would like to monitor a chemical reaction as a function of time. So you would want to measure the spectrum every ten microseconds in order to see how some product develops.”
We look at the rise of quantum computing in this second film from our series about technology spin-offs from fundamental physics research. Such devices, which would exploit superposition, entanglement and other quantum phenomena to perform super-fast calculations, have the potential for some amazing feats. But in the pursuit of a practical quantum computer, big challenges still remain.
The film was recorded at the University of Sussex in the UK where physicists are developing an approach known as ion trap quantum computing. “A normal computer has bits and these bits encode information, so numbers and words are encoded into bits which are zero or one,” explains Winfried Hensinger, head of the Ion Quantum Technology Group. “In a quantum computer, instead of having bits you have quantum bits, which can be in a superposition of zero and one – so they can be zero and one at the same time.” In the film, Hensinger provides a tour of his lab, describing how his group cools atoms down to temperatures approaching absolute zero, then traps them inside vacuum systems.
This series of films is concerned with technologies that have the potential to transform lives and societies. In the case of quantum computing, some of the most exciting applications might lie in the fields of biology and biochemistry, an idea that is explored in the film by the science writer John Gribbin. “When we have a quantum computer, we will be able to make very accurate computer models of processes involving chemical reactions, up to and including biological reactions,” he explains. “We will much better understand how proteins work, how genes work, and that will have tremendous implications in developing both the chemical and the biochemical technology of the future”.
This is a view shared by Laurence Pearl, a structural biologist at Sussex, who believes that the development of quantum computers is likely to attract the attention of pharmaceuticals companies, which could use them in the development of new drugs. “If it’s going to cost you £10 million to predict the drug that was going to work rather than a billion to actually develop the drug that’s going to work, I think drugs companies would go for that,” he says.
This film is one of a three-part series exploring some of the most promising technologies that are emerging from physics research. You can read about other physics spin-offs by reading the free special 25th anniversary issue of Physics World in our digital magazine or app.
Talk about going down a rabbit hole. There I was bent nearly in half, not quite on my knees, crawling through a narrow tunnel barely four feet tall that sloped down at a steep angle. Donning blue-grey overalls, waterproof boots and a hard hat with a miner’s lamp, I trod carefully to avoid catching myself on the sharp bits of rock protruding from all sides of the poorly lit, claustrophobic cavity. The sweltering heat and stifling humidity made breathing a chore, but I was not going to complain. It was a privilege to join Tullis Onstott and Maggie Lau of Princeton University, and Tom Krieft of the New Mexico Institute of Mining and Technology, on this scientific adventure. Nearly two kilometres underground, we were deep inside an active gold mine located near Johannesburg, South Africa. Our mission: to collect samples of ground water seeping through cracks in the bedrock, which Onstott’s team would later examine for living organisms that thrive where the Sun never shines.
In deep places of the Earth such as these, Onstott’s team and others have identified varieties of bacteria that challenge what we thought we knew about biology. Rather than relying directly or indirectly on photosynthesis, they instead feed off hydrogen gas and exist in underground ecosystems that have been totally disconnected from the biological cycles on the Earth’s surface for possibly tens of thousands of years. In 2011 Gaetan Borgonie from the University of Ghent in Belgium and his colleagues spotted roundworms (nematodes) living kilometres below ground level in several South African mines – the first multicellular organisms to be recovered from such depths. These discoveries have extended the biosphere of our planet considerably – and added to its biomass. But more interesting still, they might even provide clues to the biology of the early Earth before the evolution of photosynthesis, or to the nature of life on other worlds that have a different atmospheric make-up from our own.
Extreme beings
Organisms found in the deep subsurface of the Earth are among the many so-called “extremophiles” that scientists have come across over the past few decades. Others include microbes that live close to volcanic vents on the ocean floor, or on salt flats near the Red Sea. Yet more are found beneath the permafrost of the Canadian Arctic, within parched soils of the Atacama Desert in South America and even at the edges of the stratosphere. The very existence of these creatures affirms that life is a hardy phenomenon, capable of adapting to a remarkable range of environmental conditions.
Still, despite their magnificent and bewildering variety, all of these organisms are intimately connected to each other: they share the same biochemistry, inhabit the same evolutionary tree and trace their origins to a common ancestor that probably existed over three billion years ago. But to date, scientists have not uncovered a “shadow biosphere” on Earth, comprised of a radically different sort of life. Nor have they found compelling evidence of extraterrestrial life – yet.
Tiny hints Extremophiles can survive conditions lethal to most life forms on Earth. This tardigrade, for example, can survive at temperatures near absolute zero, at pressures six times those on the deepest ocean floor, and even in the vacuum of space under cosmic radiation. Their existence could give clues to life on other worlds. (Courtesy: Eye Of Science/Science Photo Library)
What researchers have done is to confirm that the ingredients of life, as well as potential habitats, exist beyond the Earth and are ubiquitous in our cosmic neighbourhood. Laboratory measurements show that amino acids – building blocks of proteins – are common in meteorites and comets. Some carbon-rich meteorites even contain components of DNA called nucleobases. Astronomical spectroscopy at optical, infrared and radio wavelengths has revealed a number of complex organic molecules in interstellar gas clouds – the birth sites of stars and their planetary retinue.
Closer to home, our neighbouring world Mars remains a prime target in the search for life beyond Earth, with growing evidence of past water flows raising the prospect of habitability sometime in its history. Likewise, the big moons of Jupiter and Saturn, especially those that might harbour subsurface oceans, continue to intrigue us.
Beyond our solar system
In recent memory, the most dramatic development in the quest to understand our place in the universe has been the identification of thousands of planets orbiting stars other than the Sun, known as extrasolar planets, or exoplanets. Using ground-based telescopes and spacecraft such as NASA’s Kepler observatory, astronomers commonly find such alien worlds by measuring a star’s wobble as unseen planets tug on it, or by registering a star’s periodic dip in brightness as a planet transits in front of it. That is a big change from merely 20 years ago, when we were certain of just one planetary system – our own. The pace of discovery has been astounding and the incredible diversity of worlds has surprised us many times over.
What is more, thanks to a suite of remarkable new instruments, we have taken the temperature of distant planets, espied water in their atmospheres and even captured the first direct pictures of alien worlds. A number of “super-Earths” have been found already – those more massive than Earth but less so than our ice giants Uranus and Neptune – and astronomers expect to find Earth-sized planets by the dozen within the next few years. Some of these will likely be in the so-called habitable zone, where the temperatures are just right for liquid water. That will inevitably bring questions about alien life to the fore. But detection will not come easy. It will take a new generation of telescopes to pin down molecules that we associate with life – such as oxygen, ozone, methane, water and carbon dioxide – in the atmosphere of a distant terrestrial world. Even if and when we succeed in identifying such telltale signs of life, we probably will not know for a while what sort of creatures might inhabit that world.
The Earth is special among its siblings in the solar system as the only planet with surface oceans and life on a planetary scale. However, it seems absurd, if not arrogant, to think that ours is the only life-bearing world in the galaxy, given hundreds of billions of other suns, the veritable cornucopia of planets and the apparent abundance of life’s ingredients. It may be that life is fairly common, but “intelligent” species are not. In any case, as the history of science has proven time and again, generalizing from a single instance often leads to misguided, if not dangerous, conclusions. So we will have to find at least one other example of life elsewhere before we can discern what is and is not unique about life on this precious bit of reformed cosmic debris.
Fantastical knot-like structures of light could soon be created in the lab thanks to calculations made by physicists in the US, Poland and Spain. They have discovered a new family of solutions to Maxwell’s equations that are knots of light that do not disperse or lose their specific topological properties as they propagate. The researchers say such knots, if made for real, could be used to trap atoms or create similar knots in plasmas or quantum fluids.
Identified by Hridesh Kedia at the University of Chicago, along with colleagues at the Polish Academy of Sciences in Warsaw and the Spanish National Research Council in Madrid, the new family of solutions to Maxwell’s equations have field lines describing all “torus knots” and “links”. Torus knots are those knots that can lie on the surface of a torus, whereas a link is a collection of such knots.
One solution involves magnetic-field lines that trace out a familiar “trefoil” knot around a torus that is aligned in the plane perpendicular to the direction of propagation of the light (see figure). As the light propagates, the knot is distorted but retains the topological property of being a trefoil knot. The electric-field lines have the same structure as the magnetic-field lines but are rotated about the propagation axis by an angle that depends upon the knot. Other solutions include cinquefoil knots and linked rings.
Knotty problem
Kedia and colleagues believe that these knots could be made in the lab using tightly focused Laguerre–Gaussian beams. These beams have been created and studied extensively because – unlike most other beams of light – they carry orbital angular momentum.
If these optical knots can be made in the lab, they could have a number of scientific applications. Physicists are already exploring how focussed Laguerre–Gaussian beams can be used to trap ultracold atoms and this latest theoretical development could lead to new ways of trapping them. Firing such knots into a plasma or quantum fluid could also result in knot-like entities propagating through those materials, thereby offering new ways of studying these states of matter.
Once the preserve of mathematicians, knot theory is playing an increasingly important role in how physicists describe the behaviour of physical systems, ranging from liquid crystals to superconductors. Most of these descriptions arise from numerical simulations of complex systems, rather than the exact solution of the equations describing the system of interest.
As you may have gathered (and if not, where have you been?) this month marks the 25th anniversary of Physics World – the member magazine of the Institute of Physics (IOP).
The issue has been available in print, online and via our apps (from the App Store and Google Play) since the start of the month to all members of the IOP, but because we want to celebrate our birthday with as many people as possible, we’re now making available a free PDF download of the entire issue to members and non-members alike. The PDF doesn’t have all the great multimedia you’ll find in the online and app versions, but it is still worth checking out.
The issue looks back at some of the highlights in physics of the last 25 years and also forward to where the subject is going next. We’ve split the bulk of the issue into five sections, each with five items (five times five being 25, of course):
Science songs in London and a series of “lightning talks” in the Equadorian capital Quito are among the many events being held today around the world to mark Ada Lovelace Day 2013. The annual celebrations, which are now in their fifth year, are held to recognize the achievements of women in science, technology, engineering and maths (STEM).
The day’s namesake Ada Lovelace is often referred to as the world’s first computer programmer. Born in 1815, Lovelace was a child of the Romantic poet Lord Byron, and was raised by her mother who encouraged her daughter to develop an interest in science, logic and mathematics. Lovelace excelled and became friends with the mathematician Charles Babbage at the University of Cambridge, who had already started drawing up plans for his famous calculating machines.
Physicists have taken another step forward in exploiting light’s vast unused potential as an information carrier. Researchers in Germany have calculated how “twisted” light beams can influence electrons inside hydrogen atoms via the beam’s orbital angular momentum. While the theory has not yet been confirmed in the lab, the team says that its work could lead to the development of a new way of storing and retrieving quantum information – something that could play a crucial role in the operation of future quantum computers.
Spin angular momentum is a familiar property of electromagnetic waves and it gives rise to light’s polarization. But electromagnetic waves – and indeed matter waves – can also possess what is known as orbital angular momentum (OAM), which means that a beam’s wavefront spirals around its propagation axis (in contrast to a plane wave, whose wavefront remains at right angles to this axis). Such a beam has an undefined phase and therefore has zero intensity at its centre.
First observed in 1992, OAM-carrying beams are known as twisted beams. They can now be routinely created in the laboratory using a variety of techniques that include the use of special holograms and phase plates. These beams are used in a number of areas of research, including optical communications. Indeed, researchers have shown that information-carrying beams with different degrees of twistedness can be transmitted simultaneously through a glass fibre, so increasing the transmission capacity of the link.
Twisted qubits
More futuristically, twisted beams might be used in quantum computers. These are devices that exploit quantum mechanics to operate on qubits – superpositions of 0 and 1. The idea would be to create qubits that are superpositions of two OAM states. Writing quantum information to the computer would involve firing a laser beam made up of photons in OAM superposition at a collection of atoms, so transferring the OAM to the atoms and storing the data. Reading out those data would then involve shining a second laser beam onto the atoms, in order to encode that beam with OAM information about the atomic state.
In the latest work, Oliver Matula of the University of Heidelberg and colleagues provide a general theoretical description of the interaction between twisted light beams and atoms. To do so, they calculate the angular distribution of emitted electrons when a twisted light beam impinges on and ionizes a hydrogen atom.
The researchers found that when the atom is placed close to the centre of the beam, the angular distribution is markedly different to that which would be produced by an incoming plane wave. In other words, the beam transfers its OAM to the electrons. However, when the atom is far from the beam’s centre, it turns out that the electron distribution is similar to that produced a by a plane wave. In this case, the researchers concluded, the twisted light beam exchanges only spin angular momentum with the electron.
Bessel beams
A theoretical description of interactions between beams of twisted light and atoms had already been published in 2010 by Jordi Mompart of the Autonomous University of Barcelona and colleagues in Spain. But that work considered a more limited class of “paraxial” waves that have a small transverse momentum. The latest work is more general because it describes the effect of so-called Bessel beams, which do not spread as they propagate and have a characteristic intensity profile made up of a series of concentric rings. These beams can, in principle, have arbitrary transverse momentum. Matula’s group calculated that when close to the paraxial limit an ultraviolet Bessel beam can transfer OAM to hydrogen atoms no more than about 100 Bohr radii (one Bohr radius being about 0.1 nanometres) from the centre of the beam, while in a non-paraxial state it can do so for atoms up to 10,000 Bohr radii from the centre.
James McGuire of Tulane University in New Orleans, US, who also works on the theory of twisted-photon–matter interactions, believes that the latest work is likely to contribute to applications in areas such as quantum information. But he cautions that experimental proof of this and related theoretical research will not come easily. “We are not yet at the point of testing these calculations, although I am optimistic that this may happen within the next few years,” he says, adding that “it is unfortunate that in this field there is not a closer relationship between people working in theory and experiment.”
Intense laser pulses
Mompart also praises the latest work, which he describes as an “excellent paper”, and agrees that it will be difficult to verify experimentally. “The ionization of atoms close to the vortex of an OAM light beam requires very intense laser pulses far beyond the limits of today’s technology,” he says. However, he adds that the Extreme Light Infrastructure, being developed in Eastern Europe, will have the required intensity.
Even with this experimental demonstration under their belts, physicists would still face significant additional hurdles in exploiting such OAM transfer inside a quantum computer. For one thing, Matula points out, the current work only considers the interaction of a twisted beam with a single atom and ignores the effect of the many other atoms that would be present inside a quantum computer. In addition, he says, thought would need to be given as to exactly how such interactions could be applied to specific quantum algorithms, such as the identification of a number’s prime factors.
Magnetic resonance imaging (MRI) at spatial resolutions of just 10 nm has been achieved for the first time. Developed by researchers at the University of Illinois at Urbana-Champaign in the US, the technique could be particularly useful for imaging biological samples. If further improved, it could even be used to image viruses and protein macromolecules.
MRI is based on nuclear magnetic resonance (NMR) and is a powerful tool that allows scientists to study the chemical composition of many different materials. This includes living tissue and as a result MRI has become a powerful diagnostic tool in medicine. The technique works by measuring the response of the nuclear magnetic moments – or spins – of a sample to external magnetic fields and electromagnetic radiation. But because the individual nuclear moments are tiny, MRI signals from small samples are weak and can be easily swamped by noise. As a result it has proven to be difficult to do MRI at spatial resolutions of less than about 1 mm, except under special circumstances.
This latest work was done by Raffi Budakian and colleagues, who attached the sample to be analysed – a tiny piece of polystyrene – to the tip of a silicon nanowire mechanical resonator. This is a small plank of silicon roughly 15 µm long and 50 nm wide. They then place this nanowire over a metal constriction 240 nm wide and 100 nm thick. By passing high-frequency electric currents through the constriction, they are able to generate the intense magnetic fields needed to do MRI.
Tiny vibrations
The team then oscillates this electric current through the constriction to generate a magnetic-field gradient that alternates at the same frequency as the nanowire vibrates. The interaction between the magnetic moments in the sample and the alternating inhomogeneous magnetic field produces tiny vibrations of the nanowire that can then be measured using an optical interferometer included in the set-up.
The Illinois team was able to successfully image hydrogen nuclear spins in the polystyrene sample using its method and obtained a 2D projection of the hydrogen density in the material with a spatial resolution as small as 10 nm.
“Another important result of our research is that we have demonstrated a new magnetic resonance protocol that allows us to apply NMR techniques to encode so-called spin noise,” explains Budakian. “That is, we encode information in the statistical fluctuations of all the nuclear spins in a sample rather than in their thermal spin polarization – as is usually the case.”
“Our technique in fact uses well established methods in MRI,” Budakian says. “Fourier-transform imaging is routinely used in MRI and is a very efficient sample-imaging technique, but the main difference in our new method is that we encode information in the spin noise rather than in the thermal polarization.”
According to the researchers, the technique could come in handy for imaging biological samples. “Our near-term goal is to achieve even higher spatial resolution and begin imaging virus particles,” adds Budakian. “We would ideally like to tomographically image virus particles in 3D and, with sufficient improvement, might even be able to image macromolecules such as proteins in the future.”
When Will Reeves embarked on a PhD in fibre optics at the University of Bath in 1999, his career path seemed assured. The communications industry was booming, companies around the world were eagerly hoovering up graduates with relevant skills, and with a telecoms-friendly PhD to add to his undergraduate degree in physics, Reeves figured it would be easy to find a job in industrial research at a large firm such as Nortel Networks. The economy, however, had other ideas. By the time he completed his PhD in 2003, the telecoms industry had gone into free fall, shedding thousands of jobs in the UK alone. “Companies were making loads of redundancies and there weren’t any jobs at all in what I’d trained for,” he recalls.
Fortunately, Reeves had a plan B. As an undergraduate at Bath, he had done a year’s industrial placement at Sharp Laboratories of Europe, where he worked on liquid-crystal displays and learned some basic clean-room techniques. On the strength of that experience, he says, he got an interview in 2003 at a small but fast-growing firm called Plastic Logic, which had been founded a little over two years earlier by researchers from the University of Cambridge’s Cavendish Laboratory. At the time, Plastic Logic was still trying to transform its founders’ novel work on plastic electronics into a marketable device, and Reeves was initially hired to develop techniques for measuring the performance of different components. A decade on, however, both the company and Reeves’ role within it have transformed almost beyond recognition. “It’s been quite a rollercoaster, and there have been times when we have been close to closing,” he says. “But I think actually [the telecoms crash] was a blessing in disguise because I’ve enjoyed this more than I would have enjoyed working in fibre optics.”
The physics of spin
Companies like Plastic Logic, which are founded in order to commercialize university-based research, are known as “spin-outs”, and they offer many different kinds of benefits. For physicists like Reeves, whose interests include both pure and commercial research, they are an attractive career option. For their academic founders, they are a way of getting good ideas out of the lab by drawing on resources and expertise from the commercial sphere. And of course, for universities and the sceptical politicians who fund them, spin-outs are a welcome sign that money spent on research can produce tangible benefits in the form of new products and jobs.
Spin-out firms are an attractive career option and a way of getting good ideas out of the lab
But as Reeves and others involved in spin-outs emphasize, such companies are not suited to everyone. Joining a young, untested company is risky, especially in the early years, when spin-outs are always in danger of running out of cash unless they can raise more money. As Kevin Arthur, chief executive of the solar-technology spin-out Oxford PV (see case study below) observes, “That’s something that really focuses your mind, and you’ve got to like that level of risk.” On the academic side, too, the spin-out route does not always make sense. “We all think from time to time that we have good ideas, but there are some pretty harsh things that go on commercially that have nothing to do with the goodness of the idea,” says Graham Cross, a physicist at Durham University whose spin-out firm, Farfield, initially struggled to turn a promising technology into a marketable product.
Physicists interested in working at spin-outs (or founding them) may also be at a disadvantage due to the simple fact that physics departments do not spawn as many spin-outs as their counterparts in the life sciences or engineering. And with some notable exceptions – including Oxford Instruments, which was spun out in 1959 and is now part of the FTSE 250 index of large UK companies – not many physics spin-outs grow big enough to employ large numbers of people. In 2009 Junfu Zhang, an economist at Clark University in Massachusetts, US, studied 903 academic entrepreneurs who had received funding from venture-capital companies, which invest in spin-outs with a strong potential for growth (see box). Of these high-growth spin-outs, Zhang found that fewer than 5% had founders who identified themselves as members of a physics department. In contrast, 45% came from engineering departments, while another 40% worked in the medical or biological sciences.
Start me up: three ways of funding a spin-out
Sales
(Courtesy: iStockphoto)
Companies that make high-value, low-sales-volume goods, such as scientific instruments, can sometimes grow “organically” by using the profits from each sale to develop new products and refine existing ones. This allows founders to maintain control over their company and its future direction, but it is unlikely to provide enough money for the company to do everything it wants to do or hire everyone it wants to hire. “I made some small profit out of it [the first microscope I sold], but I was working like a dog,” says Ahmet Oral, a physicist at Turkey’s Sabancı University and founder of the Anglo-Turkish firm NanoMagnetics Instruments. After finishing his “day job”, he says, “I was going back home and working until two, three, even four in the morning, nonstop, for about six months or so. It was hard.”
Seed money
(Courtesy: iStockphoto)
A variety of organizations, including governments, private philanthropic groups and international bodies such as the EU provide small-to-medium-sized grants for spin-outs and other early-stage companies. Although the application process for such grants is competitive, and the funds available are generally not on the same scale as business-angel or venture-capital funding (see below), they can be vital in a spin-out’s earliest stages and come with fewer strings attached. Examples in the UK include the Technology Strategy Board, the Royal Society Enterprise Fund, university-based groups such as the University Challenge Seed Fund and so-called “translational” research grants from the Engineering and Physical Sciences Research Council, although each of these organizations has different goals and rules for how monies are used. A spin-out’s parent university can also be an important source of early support by offering cheap lab space within the department or at a separate “business incubator” and by funding patent applications via the technology-transfer office.
Business angels and venture capital
(Courtesy: iStockphoto)
At the deep-pocketed end of the funding spectrum, business angels and venture capital (VC) firms provide money in exchange for a share of the business and – especially in the case of venture capital – a say in how it is run. The principal difference between them is that angels are investing their own money, while VC firms are managing funds from a large pool of investors. However, business angels also tend to invest in businesses earlier and to provide smaller amounts of money, typically around £100,000, to help a spin-out get through the difficult early period. In contrast, “most venture capitalists, even early-stage ones, won’t come in at less than a £1–1.5m equity investment”, says Brian Tanner, dean of knowledge transfer at Durham University. “The cost of due diligence [for their investors] is sufficiently high that they want to put in cash of that sort of quantum to make it worth their while.” In order to attract that kind of money, Tanner adds, companies need a proper management team as well as an idea or product with a strong potential for growth.
Russell Cowburn, a physicist who has founded spin-outs at both Durham and Cambridge universities, says that the low number of physics spin-outs is partly due to the nature of the field. “Quite often what physicists come up with is a new type of device, and then you’re immediately hitting this problem of scale where it can only be brought to market if you sell a billion of them,” he explains. Many biotech spin-outs, he adds, avoid this problem by developing a new treatment or process and then licensing it to a larger firm.
Another possible reason for physics’ low profile in the spin-out world is that there used to be a stigma associated with getting involved in commercial ventures. Brian Tanner, a Durham physicist who founded a company called Bede Scientific Instruments in 1978, remembers his university’s then-vice-chancellor telling him, “Well, if you really want to do this, young man, that’s okay – but we thought you had a good career ahead of you.” Such official discouragement is rare to non-existent these days, but Henry Snaith, the academic founder of Oxford PV, believes that in some quarters, old attitudes die hard. “There’s a certain branch of academic scientists – physicists, mathematicians, chemists – who consider that interacting with industry is inferior to doing pure science,” he says. “They think we should just be concentrating on finding out new phenomena and understanding things, and not be so worried about real-world problems.”
Lingering traces of anti-industry sentiment aside, however, the raw statistics probably give a misleading impression of physicists’ entrepreneurial opportunities. Because physics can be applied to many different areas, physicists are often involved in firms that do not, on the face of it, appear to have a strong connection to the subject. A good example is Sphere Fluidics, which was spun out of Cambridge’s chemistry department in 2010. The company was founded to commercialize a technique for rapidly analysing single cells encased within tiny droplets and, in June 2013, it won the life-sciences category of a pan-European spin-out competition. However, the firm’s chairman Andrew Mackintosh – a physicist by training, and a former chief executive of Oxford Instruments – argues that Sphere Fluidics actually has a strong link to physics. Although the firm employs chemists to create the microdroplets and biochemists to understand the processes taking place within them, the technique for manipulating and measuring the droplets relies on optical instrumentation – and that, Mackintosh says, requires physicists. “You have to put really sophisticated teams together very early on in the life of these companies,” he says. “In many, many spin-outs, there’ll be a lot of physics underneath, because it’s about measurement and instrumentation.”
Case study: Oxford PV
From left: Henry Snaith, Ed Crossland, Kevin Arthur (Courtesy: Douglas Fry)
While there is no such thing as a “typical” spin-out, the story (so far) of Oxford PV nevertheless includes some characteristic features. Based on research performed by University of Oxford physicist Henry Snaith, the firm’s core product is a type of solar photovoltaic (PV) cell that can be printed onto glass. It was spun out of Oxford in 2010 with the help of the university’s technology-transfer company, Isis Innovation, which funded its initial round of patents and brought in an experienced chief executive, Kevin Arthur, from the semiconductor industry.
Since then, the firm has raised more than £4m, including a total of £350,000 from the Technology Strategy Board (an organization funded by the UK government) and £3.45m from investment syndicates, including venture capital. Currently, scientists and technicians at its premises in a university-linked “business incubator” north of Oxford are working to improve the efficiency of the underlying solar-cell technology and to demonstrate that durable solar-PV glass can be produced on a commercial scale. One of Snaith’s former postdocs, Ed Crossland, joined the firm earlier this year as a senior research scientist, and the company plans to hire five new technologists before the end of 2013. In the future, Oxford PV hopes to license its product to manufacturers that can incorporate its energy-generating glass into the windows of skyscrapers, making it a ubiquitous feature of modern “green” architecture.
“I do solar-cell research because I believe that it’s the source of energy we need for the future. In some sense, it doesn’t matter which PV technology is successful as long as one of them is, but if no-one tries to push it, it’s not going to happen. My motivation is to try to get the technology out there.” Henry Snaith, physicist and chief scientific officer
“With a technical staff of 10–15 there’s not enough hands to do everything we want to do, so I’m still in the lab pretty much every day, whether it’s with my hands wet in the fume hoods or just overseeing what’s going on.” Ed Crossland, senior research scientist
“I really feel with this company we’re in the right place at the right time with the right technology. We’re constantly announcing updates to Henry’s technology and we’re just pushing at an open door with the construction industry, because they really want to have an energy-generating coating that they can apply to their existing materials.” Kevin Arthur, chief executive
Risks and rewards
This need for a physicist’s skills is a positive sign for students and recent graduates interested in joining a spin-out firm. There are, however, some caveats. At their inception, spin-outs are usually little more than one- or two-person operations, and slower-growing, revenue-funded firms often remain so for years. During this earliest phase, therefore, companies will only hire new employees to do work that the founders cannot. Moreover, employment contracts are likely to be short-term, stretching only as far as the spin-out’s current round of funding permits. Marcus Swann, a former postdoctoral researcher in Cross’s group at Durham, notes ruefully that when he joined Farfield as its fourth employee, he imagined that working there might offer more long-term stability than the “serial postdoc” phase of early-career academia. In the event, he says, “I’ve been employed for 13 years now but there hasn’t been any certainty over it. At a spin-out you’ve got no idea what’s going to happen – there’s absolutely no guarantee it’s going to last more than a year.”
Yet there are rewards in getting involved early. While life at a spin-out is not, in Tanner’s words, “just a matter of swanning off with a million quid and becoming very rich”, early employees of successful spin-outs can nevertheless make a fair amount of money. To attract talent, many spin-outs offer early employees a stake in the company, and someone who helps transform a company from a start-up to a major player usually ends up with what Cowburn delicately terms “very interesting share options”.
But even spin-outs with more modest outcomes have their attractions. Farfield was sold to a Swedish instrumentation company in 2010, and the future of its core technology is now uncertain. Nevertheless, Swann says that working there has given him a huge range of experiences that he would not have had if he had stayed in academia or gone to work for a bigger firm. In addition to scientific tasks such as computer modelling and developing measurement techniques, he says, he has also been involved in product development, customer support, sales and marketing, and participated in scientific collaborations with researchers in the petroleum and pharmaceutical industries. “There’s no area of the company’s existence where I haven’t had some good visibility,” he says. “From that point of view, it’s been a tremendous learning experience. I don’t feel constrained by my scientific background any more.” Tanner, whose first spin-out fell victim to the credit crunch of 2008 and was subsequently sold to a larger company, agrees. “I don’t know of anyone who’s been in that early-stage business environment being out of work for long,” he says.
What it takes
All of the people interviewed for this article agreed that working at a spin-out requires a love of variety. For example, on the day that Reeves spoke to Physics World about his work at Plastic Logic, he had spent the morning repairing a laser cutting machine, but said that other typical tasks include computer programming, meeting clients and even creative work such as designing sample content for the company’s electronic displays.
Another thing that came up frequently was an appetite – or at least a tolerance – for responsibility as well as risk. “If you join a spin-out, you are by definition going to be a key player in that company,” says Swann. “It’s difficult to say ‘no’ because you know that if you don’t do it, it doesn’t get done.” Scientists at a spin-out also have a responsibility to stay focused on the company’s product rather than pursuing interesting tangents, says Ed Crossland, who did a postdoc in Snaith’s group at the University of Oxford and is now a senior research scientist at Oxford PV.
Scientific skills are important, too, and for that reason, opportunities at spin-outs are more extensive for those with physics PhDs than they are for BSc graduates. “To any graduate thinking of doing research in a start-up company, I’d say they should do it with the mind of working for one or two years to gain experience,” says Snaith. “But if they really want to progress in research in industry, they should then come back [to university] and do a PhD.” Cowburn suggests that undergraduates who want to get some spin-out experience should approach companies about doing a specific piece of work, such as software programming or designing a circuit, rather than seeking a traditional, training-based internship.
Regardless of their level of experience, however, prospective employees should emphasize that they have certain skills because they are a quick learner, not because it is the only thing they can do. “Being attractive to an employer means you’re smart – you’re not just an expert in doing one particular thing,” says Crossland. “You need to be a problem solver who can apply your skills and talents to whatever problem the company might have.”
Ultimately, Mackintosh believes that spin-outs are exciting places for physicists to work. “If you’re prepared for a lively ride, you have no idea where that company can go,” says Mackintosh. “Even if that company folds, the experience you gain allows you to go do the same thing in another company – probably a lot better than you did it the first time.”
