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Incommensuration in quantum antiferromagnetic chain

Somendra M. Bhattacharjee·Sutapa Mukherji
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Abstract

A dimerized quantum Heisenberg or XY antiferromagnetic chain has a gap in the spectrum. We show that a weak incommensurate modulation around a dimerized chain produces a zero temperature quantum critical point. As the incommensuration wavelength is varied, there is a transition to a modulated gapless state. The critical behaviour is in the universality class of the classical commensurate-incommensurate (Pokrovsky-Talapov) transition. An analogous metal-insulator transition can also take place for an incommensurate chain.

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Somendra M. Bhattacharjee, Sutapa Mukherji. 1998-08-20. Incommensuration in quantum antiferromagnetic chain. https://doi.org/10.1088/0305-4470%2F31%2F40%2F001

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