Effective mass of liquid ³He using the melting curve data

Abstract

Measurements of dp/dt and of the liquid and solid molar volumes along the melting curve of ³He can be used to obtain information about the Fermi liquid parameter E_f=p_f²/2m^∗ of liquid ³He. The authors use data at temperatures reasonably far above the Neel temperature of the solid, but low enough so that the first finite-temperature correction term in Fermi liquid theory is not large. It is shown that, in spite of uncertainties in the solid ³He entropy because of uncertainties in the knowledge of the exchange mechanism, the melting curve data provide a check on the different sets of values for m^∗ quoted in literature. The authors also discuss the possible effect of ground state vacancies, whose existence in BCC ³He has been speculated on this analysis.