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Quantum Phase Transition in Pr2CuO4 to Collinear Spin State in Inclined Magnetic Field: A Neutron Diffraction Observation

V. P. Plakhty·S. V. Maleyev·S. V. Gavrilov·F. Bourdarot·S. Pouget·S. N. Barilo
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Abstract

In the external field slightly inclined to the $x$- or y-axis of the frustrated tetragonal atiferromagnet Pr2CuO4, a transition is discovered from the phase with orthogonal antiferromagnetic spin subsystems along [1,0,0] and [0,1,0] to the phase with the collinear spins. This phase is shown to be due to the pseudodipolar interaction, and transforms into the spin-flop phase S perp H asymptotically at very high field. The discovered phase transition holds at T=0 and is a quantum one, with the transition field being the critical point and the angle between two subsystems being the order parameter.

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V. P. Plakhty, S. V. Maleyev, S. V. Gavrilov, F. Bourdarot, S. Pouget, S. N. Barilo. 2002-07-08. Quantum Phase Transition in Pr2CuO4 to Collinear Spin State in Inclined Magnetic Field: A Neutron Diffraction Observation. https://doi.org/10.1209/epl%2Fi2003-00162-1

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