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Quantum fluctuations in the incommensurate phase of CsCuCl3 under transverse magnetic field

Tetsuro Nikuni·A. E. Jacobs
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Abstract

In low magnetic field, the stacked, triangular antiferromagnet CsCuCl3 has a helical structure incommensurate (IC) in the chain direction. The IC wavenumber (from neutron-diffraction experiments) decreases with increasing field transverse to the chains, as predicted by classical theory, but then it has a plateau almost certainly caused by quantum fluctuations. Linear spin-wave theory fails because fluctuations have particularly large effects in the IC phase. An innovative phenomenological treatment of quantum fluctuations yields a plateau at approximately the observed value and the observed fields; it predicts a transition to the commensurate phase so far not observed. Results depend sensitively on a weak anisotropy.

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Tetsuro Nikuni, A. E. Jacobs. 1997-02-21. Quantum fluctuations in the incommensurate phase of CsCuCl3 under transverse magnetic field. https://doi.org/10.1103/physrevb.57.5205

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