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Spin-polarized stable phases of the 2-D electron fluid at finite temperatures

M. W. C. Dharma-wardana·François Perrot
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Abstract

The Helmholtz free energy F of the interacting 2-D electron fluid is calculated nonperturbatively using a mapping of the quantum fluid to a classical Coulomb fluid [Phys. Rev. Letters, vol. 87, 206404 (2001)]. For density parameters rs such that rs<~25, the fluid is unpolarized at all temperatures t=T/EF where EF is the Fermi energy. For lower densities, the system becomes fully spin polarized for t<~0.35, and partially polarized for 0.35<t< 2, depending on the density. At rs ~25-30, and t ~0.35, an ''ambispin'' phase where F is almost independent of the spin polarization is found. These results support recent claims, based on quantum Monte Carlo results, for a stable, fully spin-polarized fluid phase at T = 0 for rs larger than about 25-26.

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M. W. C. Dharma-wardana, François Perrot. 2002-09-30. Spin-polarized stable phases of the 2-D electron fluid at finite temperatures. https://doi.org/10.1103/physrevlett.90.136601

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