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arXiv · 1002.2101

Phase Diagram of the Low-Density Two-Dimensional Homogeneous Electron Gas

N. D. Drummond·R. J. Needs
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Abstract

We have used quantum Monte Carlo methods to calculate the zero-temperature phase diagram of the two-dimensional homogeneous electron gas. We find a transition from a paramagnetic fluid to an antiferromagnetic triangular Wigner crystal at density parameter r_s=31(1) a.u. and a transition to a ferromagnetic crystal at r_s=38(5) a.u. The fully spin-polarized fluid is never stable. We searched for, but did not find, the ferromagnetic hybrid phase proposed by H. Falakshahi and X. Waintal [Phys. Rev. Lett. 94, 046801 (2005)].

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N. D. Drummond, R. J. Needs. 2010-02-10. Phase Diagram of the Low-Density Two-Dimensional Homogeneous Electron Gas. https://doi.org/10.1103/physrevlett.102.126402

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