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Nonadiabatic Approach to Spin-Peierls Transitions via Flow Equations

Goetz S. Uhrig
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Abstract

The validity of the adiabatic approach to spin-Peierls transitions is assessed. An alternative approach is developed which maps the initial magneto-elastic problem to an effective magnetic problem only. Thus the equivalence of magneto-elastic solitons and magnetic spinons is shown. No soft phonon is required for the transition. Temperature dependent couplings are predicted in accordance with the analysis of experimental data.

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Goetz S. Uhrig. 1998-04-29. Nonadiabatic Approach to Spin-Peierls Transitions via Flow Equations. https://doi.org/10.1103/physrevb.57.r14004

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