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Elementary Excitations in Dimerized and Frustrated Heisenberg Chains

G. Bouzerar·A. P. Kampf·G. I. Japaridze
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Abstract

We present a detailed numerical analysis of the low energy excitation spectrum of a frustrated and dimerized spin $S=1/2$ Heisenberg chain. In particular, we show that in the commensurate spin--Peierls phase the ratio of the singlet and triplet excitation gap is a universal function which depends on the frustration parameter only. We identify the conditions for which a second elementary triplet branch in the excitation spectrum splits from the continuum. We compare our results with predictions from the continuum limit field theory . We discuss the relevance of our data in connection with recent experiments on $CuGeO_{3}$, $NaV_2O_5$, and $(VO)_2P_2O_7$.

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G. Bouzerar, A. P. Kampf, G. I. Japaridze. 1998-06-17. Elementary Excitations in Dimerized and Frustrated Heisenberg Chains. https://doi.org/10.1103/physrevb.58.3117

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