In - situ Lorentz TEM Cooling Study of Magnetic Domain Configurations in
نویسندگان
چکیده
Magnetic domain configurations in the ferromagnetic shape memory alloy Ni2MnGa are analyzed by means of Lorentz microscopy and noninterferometric phase reconstruction methods. Domain structures in the cubic phase consist of cross-tie walls in the thinnest portions of the foil, and more complex configurations in thicker regions. At low temperature, the magnetization configurations change as the structure transforms martensitically to a tetragonal phase. A simple model for the magnetization changes is proposed.
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