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Raman Scattering from Frustrated Quantum Spin Chains

Wolfram Brenig
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Abstract

Magnetic Raman scattering from a frustrated spin-1/2 Heisenberg-chain is considered with a focus on the uniform phase of the spin-Peierls compound CuGeO_3. The Raman intensity is analyzed in terms of a Loudon-Fleury scattering process using a spinless-fermion mean-field theory developed for the frustrated spin-chain. A comparison to experimental data is presented and the frustration and temperature dependence is studied. In good agreement with observed spectra a broad inelastic four-spinon continuum is found at low temperatures above the spin-Peierls transition. At high temperatures the intensity develops a quasi-elastic line analogous to experiment.

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Wolfram Brenig. 1997-02-24. Raman Scattering from Frustrated Quantum Spin Chains. https://doi.org/10.1103/physrevb.56.2551

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