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Catastrophic Fermi surface reconstruction in the shape-memory alloy AuZn

P. A Goddard·J. Singleton·R. D. McDonald·N. Harrison·J. C. Lashley·H. Harima·M. -T. Suzuki
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Abstract

AuZn undergoes a shape-memory transition at 67 K. The de Haas van Alphen effect persists to 100 K enabling the observation of a change in the quantum oscillation spectrum indicative of a catastrophic Fermi surface reconstruction at the transition. Coexistence of both Fermi surfaces at low temperatures is suggestive of an intrinsic phase separation in the bulk of the material. In addition, a Dingle analysis reveals a sharp change in the scattering mechanism at a threshold cyclotron radius, which we suggest to be related to the underlying microstructure that drives the shape-memory effect.

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P. A Goddard, J. Singleton, R. D. McDonald, N. Harrison, J. C. Lashley, H. Harima, M. -T. Suzuki. 2005-01-06. Catastrophic Fermi surface reconstruction in the shape-memory alloy AuZn. https://doi.org/10.1103/physrevlett.94.116401

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