ZhETF, Vol. 119,
p. 107 (January 2001)
(English translation - JETP,
Vol. 92, No. 1,
available online at www.springer.com
CORRELATION EFFECTS IN THE HEAT CAPACITY OF SEPARATING 3He-4He SOLID SOLUTIONS
Antsygina T.N., Chishko K.A., Slusarev V.A.
Received: April 25, 2000
We propose to describe the impurity heat capacity of solid 3He-4He mixtures both below and above the phase separation temperature Ts by an extension of the Bethe-Guggenheim approximation for the lattice gas model. It is shown that at T>Ts, the temperature behavior of the heat capacity is completely defined by correlation effects in the impurity subsystem. The developed theory enables us to explain from the common standpoint the experimental data by Edwards, McWilliams, and Daunt for all concentrations of 4He and make some conclusions about the structure of second phase nuclei.