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One-dimensional spin-1/2 Heisenberg antiferromagnet in a weak external magnetic field

Ping Sun·D. Schmeltzer
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Abstract

The one dimensional spin-1/2 Heisenberg antiferromagnet in a weak magnetic field h is studied using the bosonization method. We derive a set of renormalization group equations. The fixed point is reached when the field is scaled to the value at which the system is quarter-filled. As the magnetic field varies, a continuum line of fixed points is formed. We compute the uniform longitudinal susceptibility $χ_z(h)$. The singular behavior of $χ_z(h)$ as $h\to 0$ is found to be contained in $1/\ln(h_o/h)$ with $h_o$ a non-universal constant. The spin-spin correlations in the magnetic field are calculated.

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Ping Sun, D. Schmeltzer. 2000-02-07. One-dimensional spin-1/2 Heisenberg antiferromagnet in a weak external magnetic field. https://doi.org/10.1103/physrevb.61.349

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