David Lee American physicist Ask the Chatbot a Question More Actions Print Cite verifiedCite While every effort has been made to follow citation style rules, there may be some discrepancies. Please refer to the appropriate style manual or other sources if you have any questions. Select Citation Style MLA APA Chicago Manual of Style Copy Citation Share Share Share to social media Facebook X URL https://www.britannica.com/biography/David-M-Lee Feedback External Websites Feedback Corrections? Updates? Omissions? Let us know if you have suggestions to improve this article (requires login). Feedback Type Select a type (Required) Factual Correction Spelling/Grammar Correction Link Correction Additional Information Other Your Feedback Submit Feedback Thank you for your feedback Our editors will review what you’ve submitted and determine whether to revise the article.

　　External Websites Nobelprize.org - Biography of David M. Lee Britannica Websites Articles from Britannica Encyclopedias for elementary and high school students. David M. Lee - Student Encyclopedia (Ages 11 and up) Ask the Chatbot a Question Also known as: David Morris Lee Written by The Editors of Encyclopaedia Britannica Encyclopaedia Britannica's editors oversee subject areas in which they have extensive knowledge, whether from years of experience gained by working on that content or via study for an advanced degree.... The Editors of Encyclopaedia Britannica Article History Table of Contents Table of Contents Ask the Chatbot Quick Facts In full: David Morris Lee (Show more) Born: January 20, 1931, Rye, New York, U.S. (age 94) (Show more) Awards And Honors: Nobel Prize (1996) (Show more) Subjects Of Study: helium-3 superfluidity (Show more) See all related content

　　heliumThe many uses for helium, but are we running out of it?(more)See all videos for this articleDavid Lee (born January 20, 1931, Rye, New York, U.S.) is an American physicist who, with Robert C. Richardson and Douglas D. Osheroff, was awarded the Nobel Prize for Physics in 1996 for their joint discovery of superfluidity in the isotope helium-3.

　　Lee received a bachelor’s degree from Harvard University in 1952 and a Ph.D. in physics from Yale University in 1959. He joined the faculty of Cornell University (Ithaca, New York) in 1959, becoming a full professor in 1968 and professor emeritus in 2007. Two years later he began teaching at Texas A&M University.

　　Lee and Richardson built a special cooling apparatus for their research in the low-temperature laboratory at Cornell. They discovered superfluidity in helium-3 by accident in 1972. They had cooled that compound to within a few thousandths of a degree above absolute zero (−273 °C) when Osheroff, a graduate student working with them, noticed odd changes in the sample’s internal pressure. The team eventually determined that these deviations marked helium-3’s phase transition to superfluidity. Because the atoms in superfluid helium-3 move in a coordinated manner, that substance lacks all internal friction and flows without resistance. Helium-3 in this state behaves according to quantum mechanical laws. The discovery of superfluidity in helium-3 enabled scientists to study directly in macroscopic (visible) systems the strange quantum mechanical effects that previously could only be studied indirectly in molecules, atoms, and subatomic particles.

　　Britannica Quiz Physics and Natural Law The Editors of Encyclopaedia BritannicaThis article was most recently revised and updated by Encyclopaedia Britannica.