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Exact spin dynamics of the 1/r^2 supersymmetric t-J model in a magnetic field

Mitsuhiro Arikawa·Yasuhiro Saiga
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Abstract

The dynamical spin structure factor S^{zz}(Q,omega) in the small momentum region is derived analytically for the one-dimensional supersymmetric t-J model with 1/r^2 interaction. Strong spin-charge separation is found in the spin dynamics. The structure factor S^{zz}(Q,omega) with a given spin polarization does not depend on the electron density in the small momentum region. In the thermodynamic limit, only two spinons and one antispinon (magnon) contribute to S^{zz}(Q,omega). These results are derived via solution of the SU(2,1) Sutherland model in the strong coupling limit.

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Mitsuhiro Arikawa, Yasuhiro Saiga. 2006-07-18. Exact spin dynamics of the 1/r^2 supersymmetric t-J model in a magnetic field. https://doi.org/10.1088/0305-4470%2F39%2F34%2F001

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