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arXiv · 0801.4075

Competition between Pomeranchuk instabilities in the nematic and hexatic channels in a two-dimensional spinless Fermi fluid

Daniel G. Barci·Marta Trobo·Victoria Fernández·Luis E. Oxman
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Abstract

We study the competition between the nematic and the hexatic phases of a two-dimensional spinless Fermi fluid near Pomeranchuk instabilities. We show that the general phase diagram of this theory contains a bicritical point where two second order lines and a first order nematic/hexatic phase transition meet together. We found that at criticality, and deep inside the associated symmetry broken phases, the low energy theory is governed by a dissipative cubic mode, even near the bicritical point where nematic and hexatic fluctuations cannot be distinguished due to very strong dynamical couplings.

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Daniel G. Barci, Marta Trobo, Victoria Fernández, Luis E. Oxman. 2008-06-21. Competition between Pomeranchuk instabilities in the nematic and hexatic channels in a two-dimensional spinless Fermi fluid. https://doi.org/10.1103/physrevb.78.035114

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