Large magnetic field induced strains in Ni Mn Ga nonmodulated martensite

Large magnetic field induced strains of up to 0.17 for a stress free Ni53.1Mn26.6Ga20.3 single crystal with nonmodulated martensite phase were generated in a rotating magnetic field. This magnetic field induced strain, which is ten times larger than values reported so far for nonmodulated martensites, evidences significant magnetic field induced twin boundary motion, which so far was thought to be impossible. This result reinforces the interest in nonmodulated martensites, which are formed as a ground state in the Heusler type ferromagnetic shape memory alloy