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Optical absorption of spin ladders

C. Jurecka·W. Brenig
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Abstract

We present a theory of phonon-assisted optical two-magnon absorption in two-leg spin-ladders. Based on the strong intra-rung-coupling limit we show that collective excitations of total spin S=0, 1 and 2 exist outside of the two-magnon continuum. It is demonstrated that the singlet collective state has a clear signature in the optical spectrum.

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C. Jurecka, W. Brenig. 1999-10-21. Optical absorption of spin ladders. https://doi.org/10.1103/physrevb.61.14307

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