イベント

千現地区 研究本館8階 中セミナー室
Sengen Main Bldg. 8F Middle Seminar Room

Prof. C.G.H. Walker

Spin and energy resolved imaging with Scanning Field-Emission Microscopy (SFEM)

Scanning Field-Emission Microscopy (SFEM) is based on STM technology, but instead of imaging in a tunneling regime the tip is retracted away from the sample surface and imaged in a field emission regime. In contrast to STM, SFEM produces secondary electrons (SE) out of the sample, which can be analyzed by different detectors such as SED, energy analyzer or spin polarimeter. This novel technique has high SE contrast and the lateral resolution can be as high as 1 nm. Spin analysis with a Mott polarimeter has shown that the SE are carrying the magnetic signature of the sample. Hysteresis loop measurements of eight monolayers Fe on top of W(011) measured with the SFEM method demonstrate a typical magnetic behavior for that model magnetic sample. Polarization images of different magnetic nano-structures will be presented and compared with the well established method of SEM with polarization analysis (SEMPA).
In addition, a new miniature electron energy analyser has been developed in association with our partners at the University of York and York Probe Sources Ltd. The intention is to operate this analyser with SFEM. Simulations and first results from this analyser using a traditional electron gun will be presented.