Open AccessAttosecond timing of the dynamical Franz–Keldysh effect
Author(s) -
Matteo Lucchini,
Shunsuke A. Sato,
Fabian Schlaepfer,
Kazuhiro Yabana,
L. Gallmann,
Ángel Rubio,
U. Keller
Publication year - 2020
Publication title -
jphys photonics
Language(s) - English
Resource type - Journals
ISSN - 2515-7647
DOI - 10.1088/2515-7647/ab70cb
Subject(s) - attosecond , electric field , physics , transient (computer programming) , dipole , dispersion (optics) , electron , phase (matter) , atomic physics , optics , quantum electrodynamics , quantum mechanics , computer science , ultrashort pulse , operating system , laser
To what extent do intra- or inter-band transitions dominate the optical response of dielectrics when pumped by a few-cycle near-infrared transient electric field? In order to find an answer to this question we investigate the dynamical Franz–Keldysh effect in polycrystalline diamond and discuss in detail the attosecond delay of the induced electron dynamics with regard to the driving transient electric field while the peak intensity is varied between 1 × 10 12 and 10 × 10 12 W cm −2 . We found that the main oscillating feature in transient absorption at 43 eV is in phase with the electric field of the pump, to within 49 ± 78 as. However, the phase delay shows a slightly asymmetric V-shaped linear energy dispersion with a rate of about 200 as eV –1 . Theoretical calculations within the dipole approximation reproduce the data and allow us to conclude that intra-band motion dominates under our experimental conditions.