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Single-hole dynamics in the t-J model

W. Apel·H. -U. Everts·U. Koerner
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Abstract

The quasi-particle weight of a single hole in an antiferromagnetic background is studied in the semiclassical approximation. We start from the t-J model, generalize it to arbitrary spin S by employing an appropriate coherent state representation for the hole, and derive an effective action for the dynamics in the long-wavelength low-energy limit. In the same limit, we find an expression for the single-hole Green's function which we evaluate in an 1/S expansion. Our approach has the advantage of being applicable in one and in two dimensions. We find two qualitatively different results in these two cases: while in one dimension our results are compatible with a vanishing quasi-particle weight, this weight is found to be finite in two dimensions, indicating normal quasi-particle behavior of the hole in this last case.

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W. Apel, H. -U. Everts, U. Koerner. 2002-08-28. Single-hole dynamics in the t-J model. https://doi.org/10.1103/physrevb.66.174423

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