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Magnetic Field Induced Ordering in Quasi-One-Dimensional Quantum Magnets

Stefan Wessel·Stephan Haas
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Abstract

Three-dimensional magnetic ordering transitions are studied theoretically in strongly anisotropic quantum magnets. An external magnetic field can drive quasi-one-dimensional subsystems with a spin gap into a gapless regime, thus inducing long-range three-dimensional magnetic ordering due to weak residual magnetic coupling between the subsystems. Compounds with higher spin degrees of freedom, such as N-leg spin-1/2 ladders, are shown to have cascades of ordering transitions. At high magnetic fields, zero-point fluctuations within the quasi-1D subsystems are suppressed, causing quantum corrections to the ordering temperature to be reduced.

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Stefan Wessel, Stephan Haas. 1999-05-21. Magnetic Field Induced Ordering in Quasi-One-Dimensional Quantum Magnets. https://doi.org/10.1007/s100510070194

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