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arXiv · 1204.6463

Coherent phonon dynamics at the martensitic phase transition of Ni_2MnGa

S. O. Mariager·A. Caviezel·P. Beaud·C. Quitmann·G. Ingold
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Abstract

We use time-resolved optical reflectivity to study the laser stimulated dynamics in the magnetic shape memory alloy Ni_2MnGa. We observe two coherent optical phonons, at 1.2 THz in the martensite phase and at 0.7 THz in the pre-martensite phase, which we interpret as a zone-folded acoustic phonon and a heavily damped amplitudon respectively. In the martensite phase the martensitic phase transition can be induced by a fs laser pulse on a timescale of a few ps.

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S. O. Mariager, A. Caviezel, P. Beaud, C. Quitmann, G. Ingold. 2012-04-29. Coherent phonon dynamics at the martensitic phase transition of Ni_2MnGa. https://doi.org/10.1063/1.4730946

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