Second Wind of the Dulong-Petit Law at a Quantum Critical Point

作者：Khodel V A^*; Clark J W; Shaginyan V R; Zverev M V

来源：JETP Letters, 2010, 92(8): 532-536.

DOI：10.1134/S0021364010200087

Renewed interest in He-3 physics has been stimulated by experimental observation of non-Fermi-liquid behavior of dense He-3 films at low temperatures. Abnormal behavior of the specific heat C(T) of two-dimensional liquid He-3 is demonstrated in the occurrence of a T-independent term in C(T). To uncover the origin of this phenomenon, we have considered the group velocity of transverse zero sound propagating in a strongly correlated Fermi liquid. For the first time, it is shown that if two-dimensional liquid He-3 is located in the vicinity of the quantum critical point associated with a divergent quasiparticle effective mass, the group velocity depends strongly on temperature and vanishes as T is lowered toward zero. The predicted vigorous dependence of the group velocity can be detected in experimental measurements on liquid He-3 films. We have demonstrated that the contribution to the specific heat coming from the boson part of the free energy due to the transverse zero-sound mode follows the Dulong-Petit Law. In the case of two-dimensional liquid He-3, the specific heat becomes independent of temperature at some characteristic temperature of a few millikelvins.

• 出版日期2010-10