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Low-energy excitations of spin-Peierls chains with modified bond-impurities

D. Augier·J. Riera·D. Poilblanc
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Abstract

The introduction of modified bond-defects in spin-Peierls systems is investigated in a model of antiferromagnetic Heisenberg spin chains coupled to adiabatic phonons. Generically, new low-energy magnetic or non-magnetic excitations appear below the bulk spin gap energy. When two adjacent bonds are modified, these excitations can be interpreted in terms of boundstates of a soliton with the localized spin-1/2 located on the impurity site. It is shown that the confining potential occurs even in the case of {\it isolated} chains.

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D. Augier, J. Riera, D. Poilblanc. 2000-01-21. Low-energy excitations of spin-Peierls chains with modified bond-impurities. https://doi.org/10.1103/physrevb.61.6741

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