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arXiv · 0709.3870

Two-mode variational Monte Carlo study of Quasiparticle excitations in cuprates

Fei Tan·Qiang-Hua Wang
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Abstract

Recent measurements of quasiparticles in hole-doped cuprates reveal highly unusual features: 1) the doping-independent Fermi velocity, 2) two energy scales in the quasiparticle spectral function, and 3) a suppression of the low energy spectral weight near the zone center. The underlying mechanism is under hot debate. We addressed these important issues by a novel two-mode variational Monte Carlo (VMC) study of the t-J model. We obtained results in agreement with the experiments but without invoking extrinsic effects. Besides, we resolved a long standing issue of the sum rule for quasiparticle spectral weights in VMC studies. The electron doped case was also discussed.

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Fei Tan, Qiang-Hua Wang. 2007-10-16. Two-mode variational Monte Carlo study of Quasiparticle excitations in cuprates. https://doi.org/10.1103/physrevlett.100.117004

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