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Unified Quantum Mechanical Picture for Confined Spinons in Dimerized and Frustrated Spin S=1/2 Chains

Goetz S. Uhrig·Friedhelm Schoenfeld·Markus Laukamp·Elbio Dagotto
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Abstract

A quantum mechanical picture is presented to describe the behavior of confined spinons in a variety of S=1/2 chains. The confinement is due to dimerization and frustration and it manifests itselfas a nonlinear potential V(x)~ |x|^b, centered at chain ends (b <= 1) or produced by modulation kinks (b > 1). The calculation extends to weak or zero frustration some previous ideas valid for spinons in strongly frustrated spin chains. The local magnetization patterns of the confined spinons are calculated. A (minimum) enhancement of the local moments of about 11/3 over a single S=1/2 is found. Estimates for excitation energies and binding lengths are obtained.

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Goetz S. Uhrig, Friedhelm Schoenfeld, Markus Laukamp, Elbio Dagotto. 1998-08-17. Unified Quantum Mechanical Picture for Confined Spinons in Dimerized and Frustrated Spin S=1/2 Chains. https://doi.org/10.1007/s100510050589

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