What do superconductor expert Paul Chu and Jimi Hendrix have in common?
They were both on stage at the “Woodstock” of their respective professions — at least according to the APS, which today celebrated the 20th anniversary of a special session on high Tc superconductivity that was held at the 1987 March Meeting in New York City.
The 1987 session occurred just months after Georg Bednorz and Alexander Muller announced their discovery of a material that was superconducting up to 35K — a much higher temperature than was thought possible. Within a year Chu had found another material that remained superconducting above liquid nitrogen temperature and the race was on to find a room temperature superconductor.
In true APS style, the 1987 special session was marked today by holding another special session called “20th Anniversary of High Tc Superconductivity ‘Woodstock’ Session” (B1), which featured many of the original lineup.
According to Brian Maple, who chaired the 1987 session, about 2200 people attended and it went on until 3.15 am — leading someone to dub it the “Woodstock Session”. Not quite the half million people that attended the four-day Woodstock music festival in 1969, but impressive for the normally staid March meeting.
The 1987 session was well attended by the media, and the speakers gained celebrity status as the world went high-Tc mad. At a press conference held today, Woodstock speaker Paul Grant produced a poster from a trendy Manhattan nightclub that had devoted an entire week to a high Tc theme. Grant said that the nightclub’s bouncers led him through the queue like a rock star. Grant also produced a high Tc t-shirt that he bought from a vendor on a California beach.
Bednorz and Muller went on to win the Nobel Prize and more than 100 high Tc compounds have since been discovered — the current record temperature being about 160K. However, Grant admits that the first real commercially viable applications of high Tc materials are still about a decade away and that “there is no generally accepted theory for high Tc superconductivity”. The latter has led to divisions within the high Tc community about the way forward.
So have the high Tc rock stars suffered the same fate as Spinal Tap?
“It’s not fair to say the theory is in great chaos”, said Woodstock attendee Douglas Scalapino when I asked him about the shortcomings of current approaches. He is confident that physicists understand the nature of the high Tc superconducting state, which he believes is caused by the “d-wave” pairing of electrons. What is not understood, says Scalapino, is why the electrons pair up in the first place and this is going to need better experimental data.
