Bradley Siwick (Chemistry and Physics, McGill)

Title: STRUCTURE AND DYNAMICS WITH ULTRAFAST ELECTRON MICROSCOPES … or how to make atomic-level movies of fundamental processes in molecules and materials.

Abstract: In this talk I will describe how combining ultrafast lasers and electron microscopes in novel ways makes it possible to directly ‘watch’ the time-evolving structure of condensed matter and the couplings between carrier and lattice degrees of freedom on the fastest timescales open to atomic motion [1-4]. By combining such measurements with complementary (and more conventional) spectroscopic probes we can now develop structure-property relationships for materials under even very far from equilibrium conditions [2]. I will assume no familiarity with ultrafast lasers or electron microscopes and highlight opportunities for theoretical/computational developments that support these experiments. Rigorous modeling of the processes described is currently intractable.
[1] Morrison et al Science 346 (2014) 445
[2] Otto et al, PNAS, 116 (2019) 450
[3] Stern et al, Phys. Rev. B 97 (2018) 165416
[4] Rene de Cotret et al, Phys. Rev. B 100 (2019) 214115