Direct determination of mode-projected electron-phonon coupling in the time domain

• DOI: 10.1126/science.aaw1662
• Publication Date: 2019-12-06T00:15:30Z
• Authors: M. X. Na; A. K. Mills; F. Boschini; M. Michiardi; B. Nosarzewski; R. P. Day; E. Razzoli; A. Sheyerman; M. Schneider; G. Levy; S. Zhdanovich; T. P. Devereaux; A. F. Kemper; D. J. Jones; A. Damascelli
• Keywords: Condensed Matter - Strongly Correlated Electrons; Strongly Correlated Electrons (cond-mat.str-el); 0103 physical sciences; FOS: Physical sciences; 01 natural sciences; 3. Good health

Ultrafast spectroscopies have become an important tool for elucidating the microscopic description and dynamical properties of quantum materials. In particular, by tracking dynamics non-thermal electrons, a material's dominant scattering processes -- thus many-body interactions between electrons collective excitations can be revealed. Here we present new method extracting electron-phonon coupling strength in time domain, means angle-resolved photoemission spectroscopy (TR-ARPES). This is demonstrated graphite, where investigate photo-injected at K point, detecting quantized energy-loss that correspond to emission strongly-coupled optical phonons. We show observed characteristic timescale spectral-weight-transfer mediated phonon-scattering allows direct quantitative extraction matrix elements, specific modes, with unprecedented sensitivity.