Steven Chu

• Born: February 28, 1948
• Place of Birth: St. Louis, Missouri

• Date of birth: February 28, 1948
• Place of birth: St. Louis, Missouri

SCIENTIST, EDUCATOR, AND GOVERNMENT OFFICIAL

Steven Chu was one of three scientists jointly awarded the 1997 Nobel Prize in Physics for discovering a technique that uses lasers to trap and study atoms. In 2009 he was appointed by President Barack Obama as the twelfth US secretary of energy. He resigned from the position in 2013.

Early Life

Physicist Steven Chu was born on February 28, 1948, in St. Louis, Missouri. His father, Ju-Chin Chu, was a chemical engineer who immigrated to the United States in 1943 from Taicang, a town near Shanghai, China; his mother, Ching-Chen Li, came to the United States to study economics at the Massachusetts Institute of Technology in 1945. Unable to return to China because of political unrest there, the couple decided to raise their family in the United States. Chu has one older brother, biochemist Gilbert Chu, and one younger brother, attorney Morgan Chu.

The son of academics, Chu was an excellent student, with a particular fondness for physics and mathematics. He also loved constructing mechanical things, which nurtured the spatial intuition that later proved valuable to him as a scientist. After graduating from high school, Chu attended the University of Rochester, where he pursued his passion for physics and mathematics. He later attributed his career as a physicist to The Feynman Lectures on Physics (1963–65), an introductory textbook by Richard P. Feynman, Robert B. Leighton, and Matthew Sands. Feynman’s use of new ideas to solve complex problems inspired Chu to want to become a theoretical physicist.

After his graduation in 1970, Chu began his graduate work at the University of California, Berkeley. His work at Berkeley convinced him that experimental research was his field of interest, and he soon began work on a doctoral thesis. During this period, a revolutionary new theory proposed a unification of two fundamental forces in the universe, electromagnetism and the weak nuclear force. Many physicists were eagerly seeking verification of this theory. Chu built a laser to study atomic transitions and the absorption of right and left polarized light. After receiving his doctorate in 1976, he remained at Berkeley to complete this project. A few months before Chu and his collaborators gathered their evidence for neutral weak interactions into print, scientists working with the Stanford Linear Accelerator uncovered the confirmatory evidence and published their results.

Life’s Work

Although Chu was part of the faculty at Berkeley, he was encouraged to take a position elsewhere in order to expand and deepen his expertise. In the fall of 1978, Chu joined Bell Telephone Laboratories in New Jersey, where he worked as an independent researcher. Chu undertook a spectroscopic study of positronium, an atom composed of an electron and its antiparticle (a positron, or positively charged electron). Previous attempts to study the properties of positronium had failed because of its extremely brief existence. By developing improved laser techniques, Chu and his colleagues were able to study a few of these atoms, and, later, even larger quantities, culminating in one of the most precise measurements of a quantum electrodynamic atomic system. Chu’s success in this study led to him being named as head of Bell’s Quantum Electronic Research Department in 1983.

In 1984, Chu developed the technique of laser cooling and trapping atoms. His 1985 paper reporting his results, “Three-Dimensional Viscous Confinement and Cooling of Atoms by Resonance Radiation Pressure,” was published in the academic journal Physical Review Letters. The central feature of Chu’s method was confining the atom under study in a space, or “box,” created by three pairs of laser beams. This technique proved to be extraordinarily valuable in studying other “optically trapped atoms.” In 1987, Chu accepted a professorship at Stanford University, where he extended his laser technique to new applications, investigating different parts of molecules and using laser beams as “optical tweezers.” He also used this method to study DNA molecules. In 1997, Chu won the Nobel Prize in Physics, which he shared with two other scientists who had helped create the method of cooling and trapping atoms with lasers.

Chu is also involved in energy issues. He encourages students to become involved in combating global climate change, which he sees as potentially devastating to American agriculture if it continues unabated. He pursued these concerns as director of the Lawrence Berkeley National Laboratory, a position he assumed in 2004. Chu succeeded in making the laboratory a center of research on energy problems. The lab worked closely with US Department of Energy.

In 2009, Chu was named the twelfth US secretary of energy by President Barack Obama. He was the first Nobel Prize winner appointed to the position. As energy secretary, Chu worked to carry out President Obama’s plans to develop wind, solar, geothermal, and other renewable energy sources, while also emphasizing efforts to increase the energy efficiencies of motor vehicles, buildings, and industries. In February 2013, he was the designated survivor during Obama’s State of the Union address.

Chu resigned as secretary of energy in April 2013, having announced his intent to resign at the beginning of February. He had remained in the position for just over four years, making him the longest-serving US energy secretary to date. Following his resignation, Chu returned to Stanford University, where he accepted the position of William R. Kenan Jr. Professor of Humanities and Sciences, a joint appointment in Stanford's Department of Physics and the School of Medicine's Department of Molecular and Cellular Physiology. Between 2019 and 2020, as he had continued giving public opinions regarding climate change, he additionally served as the president of the American Association for the Advancement of Science (AAAS).

In 2024, the American Institute of Physics awarded Chu the Karl Taylor Compton Medal for Leadership in Physics. The award, named after a prominent twentieth-century American physicist, was awarded every two years to a physicist who has made significant contributions to statesmanship and science.

Significance

Chu’s discovery of atom cooling and trapping has led to many applications, such as highly sensitive gyroscopes and an instrument that can measure gravity more precisely than any previous technique. Over the course of his career, Chu has helped develop new ways to manipulate DNA molecules, and his method has proved valuable in the study of many other molecules important in the structure and functioning of living things. Environmentalists and others concerned about the United States’ overreliance on fossil fuels believe that Chu’s advocacy of alternative energy and nuclear power has proved significant.

Bibliography

Chu, Steven. Interview. By Mike May. American Scientist, Jan.–Feb. 1998, pp. 22–25. Discusses Chu’s work with atom cooling and its applications in accessible terms.

Chu, Steven. “Steven Chu—Biographical.” Nobelprize.org, Nobel Media, www.nobelprize.org/nobel‗prizes/physics/laureates/1997/chu-bio.html. Accessed 1 May 2018.

Chu, Steven. “Taking Stock: Steven Chu, Former Secretary of the Energy Department, on Fracking, Renewables, Nuclear Weapons, and His Work, Post–Nobel Prize.” Interview by Dan Drollette Jr. Bulletin of the Atomic Scientists, vol. 72, no. 6, 2016, pp. 351–58. Academic Search Complete, search.ebscohost.com/login.aspx?direct=true&db=a9h&AN=119149722&site=ehost-live. Accessed 1 May 2018.

Glanz, James. “Master of Molecule Manipulation Works on the Wild Side.” Scientists at Work: Profiles of Today’s Groundbreaking Scientists fromScience Times, edited by Laura Chang, McGraw-Hill, 2000, pp. 167–75.

Hoy, Anne Q. "Nobel Laureate Steven Chu Assumes Term as AAAS President." Science, vol. 363, no. 6429, 2019, pp. 827–29, doi:10.1126/science.363.6429.827. Accessed 21 Aug. 2024.

Mufson, Steven. "Energy Secretary Steven Chu Resigns." The Washington Post, 1 Feb. 2013, www.washingtonpost.com/business/economy/energy-secretary-steven-chu-resigns/2013/02/01/f6253df6-6cb4-11e2-ada0-5ca5fa7ebe79‗story.html. Accessed 21 May 2018.

"Steven Chu Named Winner of the 2024 AIP Karl Compton Medal." American Institute of Physics, 26 June 2024, ww2.aip.org/aip/steven-chu-winner-of-2024-aip-karl-compton-medal. Accessed 21 Aug. 2024.

Watkins, Marshall. “Energy Secretary Steven Chu to Return to Stanford.” The Stanford Daily, 22 Feb. 2013, www.stanforddaily.com/2013/02/22/energy-secretary-steven-chu-to-return-to-stanford/. Accessed 21 May 2018.

Weiner, Rachel. "Steven Chu Is the State of the Union 'Designated Survivor.'" The Washington Post, 12 Feb. 2013, www.washingtonpost.com/news/post-politics/wp/2013/02/12/steven-chu-is-designated-survivor-for-state-of-the-union/. Accessed 21 May 2018.