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Charge Stripe in an Antiferromagnet: 1d Band of Composite Excitations

A. L. Chernyshev·Steven R. White·A. H. Castro Neto
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Abstract

With the help of analytical and numerical studies of the $t$-$J_z$ model we argue that the charge stripe in an antiferromagnetic insulator should be understood as a system of holon-spin-polaron excitations condensed at the self-induced antiphase domain wall. The structure of such a charge excitation is studied in detail with numerical and analytical results for various quantities being in a very close agreement. An analytical picture of these excitations occupying an effective 1D stripe band is also in a very good accord with numerical data. The emerging concept advocates the primary role of the kinetic energy in favoring the stripe as a ground state. A comparative analysis suggests the effect of pairing and collective meandering on the energetics of the stripe formation to be secondary.

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A. L. Chernyshev, Steven R. White, A. H. Castro Neto. 2001-11-24. Charge Stripe in an Antiferromagnet: 1d Band of Composite Excitations. https://doi.org/10.1016/s0921-4526(01)01150-4

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