Role of intra-band transitions in photo-carrier generation

Physical Review B 98 , 035202 (2018)

Role of intra-band transitions in photo-carrier generation

Shunsuke A. Sato, Matteo Lucchini, Mikhail Volkov, Fabian Schlaepfer, Lukas Gallmann, Ursula Keller, Angel Rubio

We theoretically investigate the role of intra-band transitions in laser-induced carrier-generation for different photon energy regimes: (i) strongly off-resonant, (ii) multi-photon resonant, and (iii)resonant conditions. Based on the analysis for the strongly off-resonant and multi-photon resonant cases, we find that intra-band transitions strongly enhance photo-carrier generation in both multiphoton absorption and tunneling excitation regimes, and thus, they are indispensable for describing the nonlinear photo-carrier generation processes. Furthermore, we find that intra-band transitions enhance photo-carrier generation even in the resonant condition, opening additional multi-photon excitation channels once the laser irradiation becomes sufficiently strong. The above findings suggest a potential for efficient control of photo-carrier generation via multi-color laser pulses through optimization of the contributions from intra-band transitions.

Additional Information

Preprint - 933.14 KB
This work was supported by the European Research Council (ERC-2015-AdG-694097), Grupos Consolidados (IT578-13), European Union's H2020 programme under GA no.676580 (NOMAD) and National Center of Competence in Research Molecular Ultrafast Science and Technology (NCCR MUST) funded by the Swiss National Science Foundation. S.A.S gratefully acknowledges the fellowship by the Alexander von Humboldt Foundation.

Related Projects

Related Research Areas