Stanford Today Edition: January/February, 1997 Section: Features: His Beaker Runneth Over WWW: His Beaker Runneth Over


Science and Medicine

His Beaker Runneth Over

PHYSICIST DOUGLAS OSHEROFF WINS NOBEL PRIZE

By David F. Salisbury

The phone call came, as they usually do, in the middle of the night.

"Is this Douglas Osheroff?" a voice inquired politely.

"Yes, this is Douglas Osheroff! Do you know that it's 2:30 in the morning!"

The caller apologized but said he had a matter of "considerable urgency" to discuss. When he rattled off his name - Carl Olof Jacobson - and said he was calling from Stockholm, physicist Doug Osheroff "suddenly realized what was going on."

The Royal Swedish Academy of Sciences was calling to inform him that he had been chosen to share this year's Nobel Prize in physics for his role in the discovery of superfluidity in helium-3.

That Oct. 9 call came 24 years after Osheroff himself made a portentous middle-of-the-night call about the discovery that eventually would lead to the Nobel. On April 20, 1972, graduate student Osheroff was working with physicists David Lee and Robert Richardson in the ultra-low-temperature lab at Cornell University, exploring an unexpected behavior of helium-3, an uncommon isotope of the element helium.

At 2:40 that morning, Osheroff jotted a line in his lab notebook indicating that he and his advisers had found something extremely significant: the point at which helium-3 changes from an ordinary liquid into an extraordinary substance called a superfluid. When it is a superfluid, a liquid moves without any resistance: It is arguably the closest thing to perpetual motion that occurs in nature.

Before that night, superfluidity had been discovered in only one other liquid, helium-4, though researchers had looked for this condition in helium-3 without success.

"I still get goose bumps just thinking about it," recalls Osheroff, 51, now the J.G. Jackson and C.J. Wood Professor of Physics. "It was an exciting moment. There was absolutely nobody else in the entire building to share my discovery with. So I waited an hour, until I couldn't stand it any longer, and then I called my advisers."

Those advisers, Lee and Richardson, shared the Nobel with Osheroff.

Osheroff's journey toward the prize began in Aberdeen, a small logging town in Washington state, where he was born and raised, the son of a doctor and a nurse.

"I think I was genetically predisposed to become a scientist," Osheroff says. "As a child, I got into all kinds of things, many of which would get me into trouble with the FBI today."

At 6, he was taking apart his toys to study the electric motors that powered them. At 10, playing with old telephone parts, he discovered that you could get quite a shock by hooking up a solenoid to a battery. As a high school student he built a 100,000-volt X-ray machine out of secondhand parts.

As an undergraduate at Caltech, Osheroff discovered his niche in low-temperature physics. He went on to Cornell for graduate study, where he met biochemistry graduate student Phyllis Liu when she dropped by his lab to borrow some liquid nitrogen. They were married in 1970.

A year later, Osheroff began working on the experiment on the magnetic properties of solid helium-3. The work required a very powerful magnet, which another group of graduate students had appropriated.

Serendipity intervened when, while awaiting the magnet's return, Osheroff decided to pass the time running some simple experiments.

He was testing a chamber that contained a mixture of liquid and solid helium-3, charting how the pressure in the cell varied as the liquid was converted to solid at a constant rate. Because the pressure is uniquely related to the temperature, this allowed him to measure the rate at which the helium-3 was cooling. "A lot of my fellow students thought I was wasting my time," he said.

But just before Thanksgiving in 1971, he noticed a glitch in the graph: a point where the cooling rate suddenly slowed to one-third its previous value. At first he thought it was a problem with the equipment. But when he repeated the experiment, starting with different proportions of solid and liquid, the change took place at precisely the same pressure.

"Then I knew we'd found something fundamental, I just didn't know what," he said.

Although they recognized that they had detected something real, the Cornell team's first explanation was incorrect. They attributed it to a change in the solid helium-3 ice, rather than in the liquid. Nevertheless, their paper was accepted and published.

But they were not satisfied with their explanation because it didn't quite fit the observations. More studies using the magnet showed that they had found a change in the liquid phase - they had discovered superfluidity in helium-3.

Superfluidity is unlike any familiar physical condition. When helium is placed in a beaker and cooled to a temperature close to absolute zero, it changes into a substance that defies gravity by creeping up the walls and out of the container. If the container is spinning during the cooling process and then stopped, the superfluid will continue to spin as long as it is kept cold enough.

Exploring the behavior of such matter is "pretty esoteric" research, Osheroff acknowledges. "There are no foreseeable commercial applications."

Yet scientists can learn a great deal about physical systems by studying their behavior in extremes. Superfluid helium-3, for example, has become an important model system that has increased scientists' understanding in a number of areas, including the nature of superconductors.

In one of its most unusual applications, scientists at Helsinki University have used helium-3 to test models of the primordial universe as it expanded and cooled after the Big Bang. According to the researchers, the transition from normal liquid to superfluid in helium-3 has a number of properties that are remarkably similar to the way in which matter condensed out of energy during this early period.

The Cornell team's 1972 discovery touched off a period of intensive research into the nature of this strange new substance. After getting his doctorate at Cornell, Osheroff moved to AT&T (now Lucent Technologies) Bell Laboratories where he played a major role in these investigations.

Bell colleague William Brinkman recalls that "Doug has exceptional control of even the most complex experiments and can make them work."

Brinkman notes that one of the new Nobelist's most amazing abilities is the way that he can recite long poems, such as Poe's The Raven and Service's The Cremation of Sam McGee, from memory. "It's a measure of his mental ability that he can remember all those lines after downing several drinks," he said.

The 15 years at Bell Labs were some of the most enjoyable and productive in his life, Osheroff says. But his wife thought he would make a good teacher and urged him to take a job at a university. Finally, she was offered a job in the Bay Area by Genentech that he describes as "too good to turn down."

With this impetus, the physicist sought a position at Stanford. After signing on, he quickly discovered that he couldn't spend as much time in the laboratory as he had at Bell Labs. But he says that working with students is a major compensation.

"I tell my students that they are like my children," said Osheroff, who doesn't have any of his own. "And Phyllis and I will come visit them when we're old."

His devotion to students was recognized in 1991 when he was awarded Stanford's highest teaching award, the Walter J. Gores Award for Excellence in Teaching. The importance he places on teaching is reflected in a promise that he made to himself that if he ever received a Nobel Prize and had a class scheduled that day he would teach the class. And he did.

Osheroff, who also won one of the first of the prestigious MacArthur "genius" grants, continues to study the intricacies of the helium-3 system. But he and his students also have turned their attention to the behavior of glassy materials at ultra-low temperatures.

Thirty years ago, scientists thought that various glassy materials would behave in much different ways when cooled to low temperatures. But they have found that materials as different as window glass and Mylar exhibit some common characteristics. These surprising features have made such materials a "very exciting" new subject, the physicist says.

To Osheroff, these materials show that interesting science is always just waiting to be found: "In the latest Calvin and Hobbes book," he notes, "Calvin says, 'Treasure is everywhere.' And treasure is physics." ST