Single crystal growth and characterization for thermoelectric and topological materials

Date

Aug 13, 2018

Time

11:30 AM - 12:30 PM

Speaker

Prof. Xinlin Yan

Affiliation

Technische Universität Wien, Institut für Festkörperphysik

Language

en

Main Topic

Materialien

Other Topics

Materialien, Physik

Host

Kerstin Höllerer

Description

The use of single crystals is vital for the study of tensor properties of materials and for the study where the effects from the grain boundaries and secondary phases (in polycrystalline samples) should be eliminated. In this talk, I will present my recent work on intermetallic type-I clathrates Ba8(Cu,Ga,Ge)46, which could be promising thermoelectric materials, and half Heusler phase CePt1-xPdxBi, which could show nontrivial topology, focusing on single crystal growth, characterization, and transport properties. I will demonstrate that vacancies exist in the framework of the crystal structure of Ge-based type-I clathrates, and Ga substitution for framework atoms can fill these vacancies, which increases the charge carrier mobility strongly and thus leads to enhanced thermoelectric performance. In the half Heusler system CePt1-xPdxBi, the isostructural, isoelectronic, and isosize substitution of Pt by Pd is likely to change only the spin-orbit coupling (SOC), which is a very important parameter to stabilize the topologically nontrivial electronic states, due to the large mass difference between Pt and Pd. We observe a semiconductor to metallic-like/semimetal transition with increasing the Pd substitution, demonstrating the dramatic effect of the SOC.

Links

• Seminars at the IFW

Last modified: Aug 13, 2018, 2:05:36 AM