Two-body correlations and the superfluid fraction for nonuniform systems Academic Article uri icon

abstract

  • We extend the one-body phase function upper bound on the superfluid fraction f s in a periodic solid (a spatially ordered supersolid) to include two-body phase correlations. The one-body current density is no longer proportional to the gradient of the one-body phase times the one-body density, but rather it becomes j(r 1 = 1 (r 1) h/m 1 1 (r 1) + 1/N dr 2 2] (r 1, r 2) h/m 1 2 (r 1, r 2). This expression therefore depends also on two-body correlation functions. The equations that simultaneously determine the one-body and two-body phase functions require a knowledge of one-, two-, and three-body correlation functions. The approach can also be extended to disordered solids. Fluids, with two-body densities and two-body phase functions that are translationally invariant, cannot take advantage of this additional degree of freedom to lower their energy. Springer Science+Business Media, LLC 2007.

published proceedings

  • JOURNAL OF LOW TEMPERATURE PHYSICS

author list (cited authors)

  • Saslow, W. M., Galli, D. E., & Reatto, L.

citation count

  • 4

complete list of authors

  • Saslow, WM||Galli, DE||Reatto, L

publication date

  • October 2007