Finite temperature properties of a supersolid: a RPA approach

Date

2009

Authors

Stoffel, Andre
Gulacsi, Miklos

Journal Title

Journal ISSN

Volume Title

Publisher

Springer

Abstract

We study in random-phase approximation the newly discovered supersolid phase of 4He and present in detail its finite temperature properties. 4He is described within a hard-core quantum lattice gas model, with nearest and next-nearest neighbour interactions taken into account. We rigorously calculate all pair correlation functions in a cumulant decoupling scheme. Our results support the importance of the vacancies in the supersolid phase. We show that in a supersolid the net vacancy density remains constant as function of temperature, contrary to the thermal activation theory. We also analyzed in detail the thermodynamic properties of a supersolid, calculated the jump in the specific heat which compares well to the recent experiments.

Description

Keywords

Keywords: Cumulant; Finite temperatures; Nearest-neighbour interactions; Pair correlation functions; Quantum lattice gas; Random phase approximations; Supersolid; Supersolid phase; Thermal activation; Vacancy density; Helium; Thermodynamic properties; Vacancies

Citation

Source

European Physical Journal B

Type

Journal article

Book Title

Entity type

Access Statement

License Rights

DOI

10.1140/epjb/e2009-00018-6

Restricted until

2037-12-31