Hyun Soon PARK is an assistant professor, Department of Materials Science & Engineering, INHA University, Incheon, Republic of Korea.My research interest, as an electron microscopist and materials scientist, is the studies of novel phenomena of advanced materials using conventional and advanced TEM techniques (4D Electron Microscopy and Electron Holography).
TEM is a microscopy technique in which a beam of electrons is transmitted through an ultra-thin specimen, interacting with the specimen as it passes through. An image is formed from the interaction of the electrons transmitted through the specimen; the image is magnified and focused onto an imaging device, such as a fluorescent screen, or to be detected by a sensor such as s CCD camera.
Four-dimensional (4D ) ultrafast electron microscopy (UEM) permits visualization of these dynamics with atomic-scalespatial resolution and time resolution down to the femtosecond (fs) domain. Applications: phase transformation, structural dynamics, thin films, metals, electronic materials, nanomaterials
Electron holography (EH), using the wave nature of electrons, provides opportunities for directly detecting and visualizing, in real space, the phase shifts w of electron waves due to electromagnetic fields. The holograms are formed when coherent electrons illuminating the the thin specimen (object wave) were interfered with those passing through the vacuum (reference wave) using the biprisms. Applications: Alloys, Magnetic materials, Semiconductosr, Spintronics
Martensitic phase transformation in Fe, 2D elemental mapping in alloys, Electrostatic potential distribution in MOSFET, Magnetization distribution in TMR spin valve head, 3D spin distribution of skyrmion lattice in Fe-Co-Si, Magnetism at the interface in Nd-Fe-B, In situ observation as a function of temperature, current, light, etc.