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arXiv · 1711.07738

Antiferromagnetic order without recourse to staggered fields

H. C. Donker·H. De Raedt·M. I. Katsnelson
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Abstract

In the theory of antiferromagnetism, the staggered field---an external magnetic field that alternates in sign on atomic length scales---is used to select the classical Néel state from a quantum magnet, but justification is missing. This work examines, within the decoherence framework, whether repeated $local$ measurement can replace a staggered field. Accordingly, the conditions under which local decoherence can be considered a continuous measurement are studied. The dynamics of a small magnetic system is analysed to illustrate that local decoherence can lead to (symmetry-broken) order similar to order resulting from a staggered field.

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H. C. Donker, H. De Raedt, M. I. Katsnelson. 2018-07-03. Antiferromagnetic order without recourse to staggered fields. https://doi.org/10.1103/physrevb.98.014416

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