др Андреј Постњиков

12. фебруара 2020.

У оквиру семинара Лабораторије за наноструктуре Института за физику у Београду, у уторак, 18. фебруара 2020. у 14 часова у читаоници библиотеке „Др Драган Поповић“, др Андреј Постњиков (Универзитет у Лорени, Мец, Француска), одржаће предавање:

Vibration spectra of pseudobinary semiconductors


Transversal optical modes originating from vibration of particular A-C and B-C bonds in a mixed (A,B)C pseudobinary semiconductors may exhibit fine structure revealing variations of their local, or more distant, environment in the crystal. This has been grasped within the „percolation model“ by Olivier Pagès and analysed in a number of systems and particular situations, e.g., under pressure. First-principles simulations may be helpful in addressing particular structural patterns and revealing the hence resulting vibration modes. Moreover, the placement of specific vibration frequencies (e.g., related to isolated or interacting impurities) in the spectrum can be predicted. An overview will be given of joint experimental – theoretical works done in the laboratory over last years.