Graduate Seminar

Graduate Seminar
Lecturer:

Michael Shentcis

Affiliation:

Viterbi Faculty of Electrical Engineering, Technion

Tunable free-electron X-ray radiation from van der Waals materials

Tunable sources of X-ray radiation have numerous applications for X-ray imaging and spectroscopy in fundamental science, medicine, and many areas in industry. However, despite their importance, X-ray sources used for such applications still require large facilities that have very limited accessibility, a severe limitation that therefore motivates research into other mechanisms of tunable X-ray generation. We demonstrate the ability of van der Waals (vdW) materials to serve as a robust platform for tunable X-ray generation when irradiated by moderately relativistic electrons available from a transmission electron microscope (TEM). The radiation spectrum can be precisely controlled by tuning the acceleration voltage of the incident electrons, and also by a newly introduced approach – adjusting the lattice structure of the vdW material. We present experimental results for both methods, observing energy tunability of X-ray radiation from vdW materials WSe2, CrPS4, MnPS3, FePS3 and NiPS3. Our findings demonstrate the concept of material design at the atomic level, using for example vdW heterostructures and other atomic superlattices, for realizing tunable sources of X-ray radiation on a table-top footprint.   *     M.Sc. student under the supervision of Professor Ido Kaminer.

Date: Wed 11 Dec 2019

Start Time: 12:30

End Time: 13:30

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