Coherent phonon dynamics at the martensitic phase transition of Ni_2MnGa

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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References in corpus (6)

• Adaptive modulations of martensites
• Anomalous vibrational effects in non-magnetic and magnetic Heusler alloys
• Combined experimental and theoretical investigation of the premartensitic transition in Ni${}_2$MnGa
• A First-Principles Investigation of Phonon Softenings and Lattice Instabilities in the Shape-Memory System Ni${}_2$MnGa
• Structural and magnetic dynamics of a laser induced phase transition in FeRh
• Observation of Phasons in Magnetic Shape Memory Alloy Ni2MnGa

Cited by in corpus (3)

• Premartensite to martensite transition and its implications on the origin of modulation in Ni2MnGa ferromagnetic shape memory alloy
• Structural and Magnetic Dynamics in the Magnetic Shape Memory Alloy Ni${}_2$MnGa
• Coupling between a charge density wave and magnetism in an Heusler material