Ground-state Properties of a Supersolid in RPA

Autor:	Stoffel, A. J., Gulacsi, M.
Rok vydání:	2009
Předmět:	Condensed Matter - Other Condensed Matter Condensed Matter - Statistical Mechanics
Zdroj:	Eur. Phys. J. B 68, 79 (2009)
Druh dokumentu:	Working Paper
DOI:	10.1140/epjb/e2009-00079-5
Popis:	We investigate the newly discovered supersolid phase by solving in random-phase approximation the anisotropic Heisenberg model of the hard-core boson ${}^4$He lattice at zero temperature. We include nearest and next-nearest neighbor interactions and calculate exactly all pair correlation functions in a cumulant decoupling scheme. We demonstrate the importance of vacancies and interstitials in the formation of the supersolid phase. The supersolid phase is characterised by strong quantum fluctuations which are taken into account rigorously. Furthermore we confirm that the superfluid to supersolid transition is triggered by a collapsing roton minimum however is stable against spontaneously induced superflow, i.e. vortex creation. Comment: 10 pages, 8 figures
Databáze:	arXiv
Externí odkaz:	http://arxiv.org/abs/0911.1220 Zobrazit plný text záznamu View this record from Arxiv