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Monday, August 31, 2020

Myriam Sarachik Never Gave Up on Physics - The New York Times

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In 1963, Myriam P. Sarachik tackled a big question in her field.

For decades, physicists had noticed certain metallic materials exhibited odd behavior in electrical resistance — the amount of sluggishness to the flow of electricity.

Usually, the warmer a metal is, the more that electrons bounce off the metal’s vibrating atoms, making it more difficult for a current to pass through. Typically, as a metal cools, the vibrations diminish, the electrons move more readily, and the resistance drops.

But sometimes as some metallic materials are chilled even colder, the electrical resistance starts rising again. It was a mystery.

The phenomenon is now known as the Kondo effect, after Jun Kondo, a Japanese physicist who successfully explained what was going on. The Kondo effect has turned out to be a central component needed to understand the behavior of electrons in solids.

But Dr. Kondo, as a theorist and not an experimentalist, was not the first to show that his supposition was correct.

That instead was Dr. Sarachik, 87, now retired after a career spanning more than a half-century as a professor of physics at the City College of New York.

The experiment was just one of the accomplishments for which Dr. Sarachik received this year’s Medal for Exceptional Achievement in Research, a top honor of the American Physical Society.

“And so here I am,” Dr. Sarachik said during a ceremony held in Washington in January. “I can’t even believe it, because I almost didn’t get into the field at all.”

Her career commenced as the United States was racing to catch up in science and space after the Soviets launched the Sputnik satellite in 1957 and the first astronaut, Yuri Gagarin, in 1961. Colleges were establishing and expanding their physics departments. Industry jobs were bountiful.

But even during this golden era of science, women like Dr. Sarachik were discouraged from participating.

Two years before her Kondo effect work, Dr. Sarachik, giving in to the expectations of the day, set aside her physics research a year after finishing her Ph.D. at Columbia University in New York. She was going to stay home and take care of Karen, her newborn daughter.

“I was home for about a month, and I realized I was never going to survive this,” she said.

Her husband, Philip, an assistant professor of electrical engineering at Columbia, urged her to return to research. She recalled him saying, “I would rather pay someone to take care of Karen than a psychiatrist.”

But when she attended a job fair at a physics conference in New York, Dr. Sarachik, unlike her Columbia classmates, received no requests for job interviews. “I got none,” she said. “I got absolutely zero. I got, again, very unhappy. So very, very unhappy.”

In despair, she reached out to one of her Columbia professors, Polykarp Kusch.

“I asked him to please help me,” Dr. Sarachik said. “He argued with me long and hard. He said, ‘You don’t really want to do what you think you want to do. You don’t want to do research. Maybe you should take a part-time teaching job.’ And I said, ‘No, I want to do research.’”

She said that at the end of the back-and-forth, Dr. Kusch gave in: “Finally he said, ‘Look, Myriam, we trained you. I don’t know why you want to do what you want to do. But if you want to do it, you have the right to try.’”

In an interview, Dr. Sarachik said of Dr. Kusch, “He had this bias. We all have it, but he was willing to operate above it.”

The next day, she received a phone call from Bell Labs, the research arm of AT&T in New Jersey, which was then a mecca for groundbreaking basic research. Dr. Sarachik said she was hired to what amounted to a two-year postdoctoral position.

Credit...via Myriam Sarachik

It was at Bell Labs that the odd electrical resistance problem caught her attention.

“And nobody knew what to make of it,” Dr. Sarachik said.

Other physicists at Bell Labs were exploring alloys containing metals like niobium, molybdenum and rhenium as well as a smidgen of iron. The small amounts of iron sometimes acted as magnets within the materials.

Dr. Sarachik investigated an aspect of these magnetic alloys, measuring how the electrical resistance changed with temperature, from close to absolute zero, minus 459 degrees, the coldest possible temperature, to about minus 350 degrees Fahrenheit.

Measuring electrical resistance is straightforward — something that students might do in a high school physics laboratory. Even the ultralow temperatures were not a technical challenge for a professional laboratory.

Still, “It seemed like a neat thing to try,” she said.

When the magnetism of the iron was present, she observed the unexplained behavior of resistance increasing with falling temperatures. When the magnetism was not present, the resistance continued to drop with the dropping temperatures.

The results caught the eye of Dr. Kondo, who had come up with calculations that suggested that as the alloy cooled, the electrons scattered more and more off the magnets of iron atoms, increasing the electrical resistance.

Dr. Sarachik said that when Dr. Kondo sent her an early version of his paper, she immediately knew that her data fit with his calculations. She thus provided the first experimental confirmation of the Kondo effect.

But her contribution was largely overlooked by others, including by her colleagues at Bell Labs.

“I got no recognition for it for years,” she said, and soon she was looking for a new job.

Dr. Sarachik said in the laboratory’s rankings of employees, she was placed in the bottom third and when her two-year appointment ended, there was no offer for her to stay. At about the same time, her husband did not receive tenure at Columbia and also needed a new job, so the two of them considered moving away from New York.

These days, married academics often talk of the two-body problem — the juggling of careers in the search of a university or company willing to hire both. It can be a convoluted balancing act, but it is commonplace. In the 1960s, that was rare. Only the husband mattered. Indeed, offering a job to the wife as well was often regarded as nepotism.

Philip Sarachik received offers to join the faculty at top-tier universities like the University of Michigan and the University of Maryland. She only received one offer of a temporary postdoctoral position, from the University of Maryland.

Philips Research Laboratories, then located just north of New York City, offered her a job. But the salary would have been thousands of dollars below what a man would earn. She objected; the company told her that was the prevailing practice toward women in the industry. She rejected the offer, even though she had no other options at the time.

Still, she persisted in physics.

“I’m not a quitter,” Dr. Sarachik said. “I couldn’t not do it.”

Credit...United Press International

Throughout a peripatetic childhood, she often did not fit in. She was born in Antwerp, Belgium, to Orthodox Jewish parents, just as Adolf Hitler was rising to power in neighboring Germany. Through false papers, bribes and an escape from a concentration camp, she, her parents and two brothers fled, first to Cuba and then to New York City. She was among the first girls to attend the Bronx High School of Science, and then she went to Barnard College, taking physics classes at Columbia.

The sciences were opening up to women, slowly, when she decided to study physics. “If I had tried 20 years earlier, I don’t think it would have been possible,” she said.

Her husband, whom she met in one of her undergraduate physics classes, encouraged her, too. “He was enormously supportive of me,” she said. “He gave me the room to do what I really wanted to do.”

When Dr. Sarachik was having trouble finding a job in 1964, Philip said it was an easy decision to pass on the offers he had until she also found a position in the same locale. “What’s the difficulty in making that kind of choice?” he said. “I had offers in a number of places so I had choices when Myriam didn’t, so it wasn’t very difficult to choose a place where we both had jobs.”

Finally, the City College of New York offered her a position as an assistant professor in 1967 while Philip joined New York University. In three years, she was promoted to associate professor with tenure. Her career thrived.

Then her younger daughter Leah was murdered.

Dr. Sarachik mentioned the loss glancingly during her talk in January. “We had a disastrous family disaster, which took me out of commission pretty much for 10, 15 years,” she said. “And some of you know about that.”

Soon after the start of the fall semester in 1970, the nanny drove the couple’s car to pick up Leah from a play date and never returned. The older daughter, Karen, then 9, was at home alone. Twelve days later, authorities found the nanny dead in the rear of the car from an overdose of sleeping pills.

A month later, Leah’s body was found in a trash can behind a summer house in Vermont.

Dr. Sarachik filled the walls of her apartment with needlework. She helped her graduate students finish their degrees. She taught some classes.

Gradually, she returned to research.

In the 1980s, as she sought to restart her efforts, one of her laboratories at the City College physics department had become a de facto storage room of junk. She sent out a memo asking people to take their belongings. No one did. She sent out another memo saying that anything not removed by the end of the week would be thrown out.

She reclaimed her space.

Laura H. Greene, chief scientist at the National High Magnetic Field Laboratory in Tallahassee, Fla., first met Dr. Sarachik around this time. Dr. Greene had just joined Bell Labs, two decades after Dr. Sarachik worked there.

“I didn’t know she was just getting back into physics,” Dr. Greene said. “I knew she had a sadness about her.”

Dr. Greene was switching from a different area of physics and needed to learn about a lot of Dr. Sarachik’s work. “She had infinite patience,” Dr. Greene said. “Really good at explaining things.”

In her second chapter of research, Dr. Sarachik became known for several paradigm-breaking experiments.

She explored how some two-dimensional materials, generally insulators that do not conduct electricity, could turn into metallic conductors, something theorists said was impossible.

“That’s way ahead of the time,” Dr. Greene said. “So she was always pushing the envelope.”

Credit...Calla Kessler for The New York Times

Theorists indeed still have not come up with a convincing explanation for what she showed.

Dr. Sarachik also led experiments that explored the quantum behavior of molecules that act like magnets. The work demonstrated that the north and south poles of these molecules, each consisting of a couple hundred atoms, could spontaneously flip at cold temperatures where such flips are forbidden by classical physics.

Other physicists had tried to show this as well. But at that time, the materials could only be made as powders. The magnetic fields of these crystal specks pointed in random directions, and the evidence was inconclusive.

One of Dr. Sarachik students, Jonathan Friedman, provided a solution by mixing the powder in a liquid glue and placing the mixture in a strong magnetic field. The crystals lined up with the magnetic field, and as the glue dried, remained pointing in that direction.

As a result, her data were clear and convincing.

“It started the whole field with big symposiums, ending up with thousands of theorists and experimentalists working in this area,” said Eugene Chudnovsky, a professor of physics at Lehman College and the City University of New York’s Graduate Center.

“The reason she is a good physicist is because she’s very clever,” said Dr. Chudnovsky, who wrote a letter nominating Dr. Sarachik for the American Physical Society medal.

At the society’s award ceremony, she reflected on her long career.

“Women are no better and no worse at doing physics than men are,” she said. “They are, however, at least if they’re my age, more persistent. It’s tenacity. It’s the will not to be pushed out.”

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