Time- and angle-resolved photoemission spectroscopy accesses the ultrafast evolution of quasiparticles and many-body interactions in solid-state systems. However, the momentum- and energy-resolved transient photoemission intensity may not be unambiguously related to the intrinsic relaxation dynamics of photoexcited electrons. In fact, interpretation of the time-dependent photoemission signal can be affected by the transient evolution of both the one-electron removal spectral function as well as the photoemission dipole matrix elements. Here we investigate the topological insulator Bi1.1Sb0.9Te2S to demonstrate, by means of a careful probe-polarization study, the transient contribution of matrix elements to the time-resolved photoemission signal.
@article{arxiv.1810.06571,
title = {Role of matrix elements in the time-resolved photoemission signal},
author = {F. Boschini and D. Bugini and M. Zonno and M. Michiardi and R. P. Day and E. Razzoli and B. Zwartsenberg and E. H. da Silva Neto and S. dal Conte and S. K. Kushwaha and R. J. Cava and S. Zhdanovich and A. K. Mills and G. Levy and E. Carpene and C. Dallera and C. Giannetti and D. J. Jones and G. Cerullo and A. Damascelli},
journal= {arXiv preprint arXiv:1810.06571},
year = {2020}
}