Electronic coherence and coherent dephasing in the optical control of electrons in graphene

Abstract

Electronic coherence is of utmost importance for the access and control of quantum-mechanical solid-state properties. Using a purely electronic observable, the photocurrent, we measure an electronic coherence time of 22 +/- 4 fs in graphene. The photocurrent is ideally suited to measure electronic coherence as it is a direct result of quantum path interference, controlled by the delay between two ultrashort two-color laser pulses. The maximum delay for which interference between the population amplitude injected by the first pulse interferes with that generated by the second pulse determines the electronic coherence time. In particular, numerical simulations reveal that the experimental data yield a lower boundary on the electronic coherence time and that coherent dephasing masks a lower coherence time. We expect that our results will significantly advance the understanding of coherent quantum-control in solid-state systems ranging from excitation with weak fields to strongly driven systems.

References in corpus (4)

• Terahertz driven extremely nonlinear bulk photogalvanic currents in non-resonant conditions
• Minimum requirements for laser-induced symmetry breaking in quantum and classical mechanics
• Adiabaticity parameters for the categorization of light-matter interaction -- from weak to strong driving
• Ab-intio study of ultrafast charge dynamics in graphene

Cited by in corpus (5)

• Ultrafast dynamics of electrons and phonons: from the two-temperature model to the time-dependent Boltzmann equation
• Doping and gap-size dependence of high-harmonic generation in graphene : Importance of consistent formulation of light-matter coupling
• Detecting light-induced Floquet band gaps of graphene via trARPES
• Light-field control of real and virtual charge carriers
• Robustness of the Floquet-assisted superradiant phase and possible laser operation