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Spin polarons in triangular antiferromagnets

Matthias Vojta
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Abstract

The motion of a single hole in a 2D triangular antiferromagnet is investigated using the t-J model. The one-hole states are described by strings of spin deviations around the hole. Using projection technique the one-hole spectral function is calculated. For large J/t we find low-lying quasiparticle-like bands which are well separated from an incoherent background by a gap of order J. However, for small J/t this gap vanishes and the spectrum becomes broad over an energy range of several t. The results are compared with SCBA calculations and numerical data.

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Matthias Vojta. 1998-11-13. Spin polarons in triangular antiferromagnets. https://doi.org/10.1103/physrevb.59.6027

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