Transmission electron microscopy on magnetic phase transformations in functional materials

This article reports our recent studies on the magnetic imaging by electron holography or Lorentz microscopy, which is combined with other supplernentary techniques related to transmission electron microscopy (TEM). By combining with dark-field imaging, the one-to-one correspondence between the magnetic domain walls and antiphase boundaries (APBs) in a ferromagnetic shape memory alloy (SMA) Ni2Mn(A1,Ga) was revealed. In order to examine both magnetism and conductivity in a nanoscale area, we have developed a double probe piezodriving holder, by which microprobes can be brought in contact with the portion of interest. The conductivity measurement can be simultaneously pet-formed with Lorentz microscopy or electron holography.