Seminar on Momentum Microscopy by Prof. Suga

Post date: Nov 18, 2015 3:46:50 AM

Prof. Suga visited NAIST on 2015, 11.18 and gave us an excellent lecture on Momentum Microscope developed in Prof. Kirschner's group. The performance of momentum microscope was impressive. Momentum Microscope seems to be a next way to go. His entire talk was very impressive probably because I could see he enjoyed science so much.

Note:

1. The basic structure is PEEM lens + hemispherical analyser x 2.

Momentum microscope gives you energy plane cuts of band structures.

By scanning the energy, you'll get the entire band structure.

2. Momentum microscope has been on sale by Focus.

http://www.focus-gmbh.com/uhv-instruments/PEEM_NanoESCA/page74/page74.html

Prof. Kirschner's version has an improved lens, which leads to better energy/ angular resolution.

Now spin detection using Au/Ir(001) is available.

Ex: Spin resolved band structure imaging with a high resolution momentum microscope

Christian Tuschea, , Alexander Krasyuka, Jürgen Kirschnera, b

http://www.sciencedirect.com/science/article/pii/S0304399115000698

3. The sample surfaces have to be fairly flat because of high voltage between sample and the entrance lens (20kV).

4. It costs around 300 million yen ( ~2.4 million $).

5. Spin orientation detected by spin ARPES for a topological Insulator depends on the photon polarization and the photon energy.

We have to be careful to talk about the spin structure in the case the initial states are not pure but composed of several atomic orbitals.