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arXiv · 1511.02483

Quantum phase transitions and decoupling of magnetic sublattices in the quasi-two-dimensional Ising magnet Co3V2O8 in a transverse magnetic field

K. Fritsch·G. Ehlers·K. C. Rule·K. Habicht·M. Ramazanoglu·H. A. Dabkowska·B. D. Gaulin
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Abstract

The application of a magnetic field transverse to the easy axis, Ising direction in the quasi-two-dimensional Kagome staircase magnet, Co3V2O8, induces three quantum phase transitions at low temperatures, ultimately producing a novel high field polarized state, with two distinct sublattices. New time-of-flight neutron scattering techniques, accompanied by large angular access, high magnetic field infrastructure allow the mapping of a sequence of ferromagnetic and incommensurate phases and their accompanying spin excitations. At least one of the transitions to incommensurate phases at \mu 0Hc1~6.25 T and \mu 0Hc2~7 T is discontinuous, while the final quantum critical point at \mu 0Hc3~13 T is continuous.

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K. Fritsch, G. Ehlers, K. C. Rule, K. Habicht, M. Ramazanoglu, H. A. Dabkowska, B. D. Gaulin. 2015-11-08. Quantum phase transitions and decoupling of magnetic sublattices in the quasi-two-dimensional Ising magnet Co3V2O8 in a transverse magnetic field. https://doi.org/10.1103/physrevb.92.180404

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