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Richardson, Richard C

quantum helium osheroff liquid

(1937–) US physicist: co-discoverer of superfluidity of helium-3.

In 1972 Richardson, David Lee (1931– ) and Douglas Osheroff (1945– ) were researchers at the Low Temperature Laboratory at Cornell. Lee had come from Harvard and Yale; Richardson had been at Duke University, NC. With Osheroff, a graduate student at Cornell, they built a cooling apparatus and observed helium-3 (the rare isotope) as it cooled to absolute zero. Osheroff noticed jumps in the sample’s pressure when a few thousandths of a degree Kelvin were reached. Together they decided that this surprising result must be due to the helium-3 undergoing a phase transition at 0.0027 K to the superfluid state. Superfluidity had first been observed by in 1938, using helium-4; it becomes superfluid at 2.17 K. However, it was a matter of debate whether the rare isotope helium-3 would behave similarly. Superfluidity is a macroscopic quantum state, where atoms behave in a coordinated rather than random manner, flowing non-viscously without friction. Instead of being independent atoms their quantum states combine to form a single quantum liquid state rather than a classical liquid of many separate atoms. The significance of their discovery was that a quantum liquid allows quantum theory to be studied on a large scale rather than on the more difficult atomic scale. Richardson, Lee and Osheroff shared the Nobel Prize for physics in 1996.

Richardson, Scovel(1912–1982) - Judge, lawyer, educator, Receives Presidential Appointments, Chronology [next] [back] Richards, Theodore William

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