New light on organic LEDs
Light emission from organic materials occurs through two separate processes: fluorescence – the process by which today’s organic semiconductors produce light – and phosphorescence. I...
Conductivity measurements made on a single strand of DNA
The Delft group fabricated the electrodes by making a slit in a silicon nitride film with standard lithography. A series of platinum layers were then sputtered across the slit until the gap was reduce...
Polymer lasers without mirrors
The waveguide structure was created by pouring a mixture of copolymer solution and molecular laser dye into a mould situated on top of a silicon wafer. The solution was allowed to solidify over 12 hou...
Top quark and Bell’s inequalities top PhysicsWeb Nobel poll
Every year the Foundation asks 3000 physicists to nominate individuals for the prize, and compiles a short-list of 250 candidates. These names are then whittled down to a list of 30, from which the wi...
Heat can produce ultrasound
Currently most ultrasound devices convert an electrical signal directly into mechanical vibrations through the piezoelectric effect. But these devices only operate over a narrow frequency range and ha...
Parisi wins Dirac medal
Parisi won the award for his work in a wide number of fields. The official citation highlights “his study of scaling violations in deep inelastic processes (Altarelli-Parisi equations), a model ...
Vortex look for lasers
Scheuer and Orenstein used so-called vertical cavity surface-emitting lasers. In these devices the light is emitted from the top of the active region of the laser, rather than from the edge as in conv...
Defects work for laser
The photonic crystal was made by using an ion beam to drill a 2D hexagonal array of holes in a layer of indium gallium arsenide phosphide (InGaAsP). The regular spacing of the holes means that only ce...
DNA is a semiconductor
Fink and Schönenberger made their measurements by placing discrete amounts of DNA molecules in a water-based solution. A tiny droplet of the solution was then placed onto a gold-coated carbon foi...
Spinach to fuel optoelectronics
Although they are only 5nm long, each complex can generate 1 V in picoseconds, making them suitable for ultrafast switching, logic devices, and solar-power generation. The work was presented this week...
