On the incommensurate phase in BaMnF4: sample dependence of the order parameter
نویسندگان
چکیده
2014 We present results concerning sample dependence of not only the modulation wave vector, but also of the amplitude of the order parameter describing the N (A21am) ~ incommensurate phase transition in BaMnF4: X-ray diffraction, Cp (« DSC »), and birefringence measurements were performed on a wide set of crystals which were synthetized by Bridgman, Czochralski, and hydrothermal methods. The existence of a tricritical point which can be reached under a 03C3vz stress is proposed, and a new interpretation of the Cp anomaly observed in 1982 by Scott, Habbal and Hidaka, is given. J. Phys. France 49 (1988) 463-469 MARS 1988,
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