Helium in Aerogel

AUG 01, 1996

A minute amount of appropriately placet impurity has fascinating effects on the nature of the superfluid transitions in helium‐4 and helium‐3, and on the ordering of ³He‐⁴He, mixtures.

DOI: 10.1063/1.881509

Moses Chan

Norbert Mulders

John Reppy

An important theme that threads through many areas of current interest in condensed matter physics is the effect of randomness and disorder. Prior to the 1960s, disorder and impurities were often viewed as unavoidable nuisances that masked the true behavior of ideal systems. We have since learned that disorder itself can bring forth fascinating and often unexpected new phenomena in condensed phases of matter. (See the December 1988 special issue of PHYSICS TODAY, dedicated to disordered solids.)

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More about the authors

Moses Chan, Pennsylvania State University, University Park.

Norbert Mulders, Pennsylvania State University, University Park.

John Reppy, Cornell University, Ithaca, New York.