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Field-induced incommensurate-to-commensurate transition in Ba_2CuGe_2O_7

A. Zheludev·S. Maslov·G. Shirane·Y. Sasago·N. Koide·K. Uchinokura
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Abstract

We report an observation of a commensurate-incommensurate phase transition in the Dzyaloshinskii-Moriya spiral antiferromagnet Ba_2 Cu Ge_2 O_7. The transition is induced by an external magnetic field applied along the c-axis of the tetragonal structure, i. e., in the plane of spin rotation. Bulk magnetic measurements and neutron diffraction experiments show that the transition occurs in a critical field Hc=2.1T. Experimental results for the period of the magnetic structure and magnetization as functions of magnetic field are in quantitative agreement with our exact analytical solution for Dzyaloshinskii's model of commensurate-incommensurate transitions in spiral magnets.

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A. Zheludev, S. Maslov, G. Shirane, Y. Sasago, N. Koide, K. Uchinokura. 1997-06-13. Field-induced incommensurate-to-commensurate transition in Ba_2CuGe_2O_7. https://doi.org/10.1103/physrevb.57.2968

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