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arXiv · 1001.0590

Influence of Thermal Fluctuations of Spin Density Wave Order Parameter on the Quasiparticle Spectral Function

M. Khodas·A. M. Tsvelik
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Abstract

The two-dimensional model of itinerant electrons coupled to an anti-ferromagnetic order parameter is considered. In the mean field solution the Fermi surface undergoes reconstruction, and breaks into disconnected ``pockets''. We have studied the effect of the thermal fluctuations of the order parameter on the spectral density in such system. These fluctuations lead to a finite width of the spectral line scaling linearly with temperature. Due to the thermal fluctuations the quasi-particle spectral weight is transfered into a magnetic Brillouin zone. This can be interpreted as restoration of ``arcs'' of the non-interacting Fermi surface.

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M. Khodas, A. M. Tsvelik. 2010-01-04. Influence of Thermal Fluctuations of Spin Density Wave Order Parameter on the Quasiparticle Spectral Function. https://doi.org/10.1103/physrevb.81.155102

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