Ensemble properties of charge carriers injected by an ultrashort laser pulse

Abstract

The average effective mass of charge carriers produced by an intense ultrashort laser pulse in a transparent solid increases significantly as the excitation mechanism changes from multiphoton transitions to interband tunneling. We theoretically investigate this phenomenon for several dielectrics and semiconductors. For diamond as a representative dielectric, we present a detailed analysis of the laser-induced change of optical properties. When the concentration of free carriers is high, we find that the average effective mass controls not only the intraband charge-carrier transport but also the interband contributions to the optical response. We observe that the excitation-induced birefringence is particularly large for parameters where the plasma response compensates for the linear response of an unperturbed solid. arXiv:1804.09030v2 [cond-mat.mes-hall] 20 Nov 2018 * vladislav.yakovlev@mpq.mpg.de 1 H. M. van Driel, Appl. Phys. Lett. 44, 617 (1984).

Transient optical properties of highly excited dielectric materials: Apparent birefringence and delayed reflectivity increase

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Optical Bloch modeling of femtosecond-laser-induced electron dynamics in dielectrics

“…But they generally do not account for the band structure beyond a single parabolic band and are currently computationally too expensive for their coupling to a Maxwell solver. First-principle approaches as time-dependent density functional theory fully describe the band structure, as well as the time-dependent interaction [32,33]. However collisions are not properly described [34,35].…”

Transient field-resolved reflectometry at 50-100 THz

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