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arXiv · 1510.08653

Spontaneous symmetry breaking in correlated wave functions

Ryui Kaneko·Luca F. Tocchio·Roser Valentí·Federico Becca·Claudius Gros
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Abstract

We show that Jastrow-Slater wave functions, in which a density-density Jastrow factor is applied onto an uncorrelated fermionic state, may possess long-range order even when all symmetries are preserved in the wave function. This fact is mainly related to the presence of a sufficiently strong Jastrow term (also including the case of full Gutzwiller projection, suitable for describing spin models). Selected examples are reported, including the spawning of N\'eel order and dimerization in spin systems, and the stabilization of charge and orbital order in itinerant electronic systems.

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Ryui Kaneko, Luca F. Tocchio, Roser Valentí, Federico Becca, Claudius Gros. 2015-10-29. Spontaneous symmetry breaking in correlated wave functions. https://doi.org/10.1103/physrevb.93.125127

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