Strong light-field effects driven by nearly single-cycle 7-fs light field in correlated organic conductors

TL;DR

This study demonstrates that nearly single-cycle 7-fs light pulses can induce transient charge localization effects in correlated organic conductors, revealing new insights into light-driven electronic state manipulation.

Contribution

It shows that ultrashort, high-frequency light pulses can induce transient charge order and localization in organic conductors, combining experimental results with theoretical insights.

Findings

Transient charge order induced in alpha-(BEDT-TTF)2I3

Red shift of plasma-like reflectivity edge in TMTTF2AsF6

Field-induced charge localization influenced by lattice and Coulomb effects

Abstract

We have demonstrated transient charge localization effects with a driving high-frequency field of 7-fs, 1.5-cycle near infrared light in correlated organic conductors. In a layered organic conductor alpha-(BEDT-TTF)2I3 (BEDT-TTF: bis[ethylenedithio]-tetrathiafulvalene), a transient short-range charge order (CO) state is induced in a metallic phase. In contrast to such drastic change in the electronic state from the metal to the transient CO in alpha-(BEDT-TTF)2I3, dynamics of a field-induced reduction of a transfer integral are captured as a red shift of the plasma-like reflectivity edge in a quasi-one-dimensional organic conductor (TMTTF)2AsF6 (TMTTF: tetramethyltetrathiafulvalene). These studies on the field-induced charge localization have been motivated by the theory of dynamical localization on the basis of tight-binding models with no electron correlation under a strong continuous field. However, the results of pump-probe transient reflectivity measurements using nearly single-cycle 7-fs, 11 MV/cm pulses and the theoretical studies which are presented in this review indicate that the pulsed field contributes to the similar phenomenon with the help of a characteristic lattice structure and Coulomb repulsion.