Ultrafast response of plasma-like reflectivity edge in (TMTTF)2AsF6 driven by 7-fs, 1.5-cycle strong-light field

TL;DR

This study demonstrates ultrafast, significant changes in the plasma-like reflectivity edge of (TMTTF)2AsF6 driven by 7-fs laser pulses, revealing rapid charge dynamics and the influence of Coulomb interactions.

Contribution

It provides the first detailed analysis of ultrafast plasma edge response in (TMTTF)2AsF6 using 7-fs pulses, linking reflectivity changes to charge mass and Coulomb effects.

Findings

20 fs response time of reflectivity edge change

3% reduction in plasma frequency due to increased charge mass

Charge gap influences plasma frequency oscillations

Abstract

The strong light-field effect of (TMTTF)2AsF6 was investigated utilizing 1.5-cycle, 7-fs infrared pulses. The ultarfast (20 fs) and large (40%) response of the plasma-like reflectivity edge (0.7 eV) was analyzed by the changes in omega_p=sqrt(ne2/(epsilon_0*epsilon(infty)*m)} (n: number of charges in the 1/4 filled-band, m: mass of charge, epsilon(infty): dielectric constants for high-frequency and vacuum, e: elementary charge). The 3% reduction in omega_p is attributed to the 6% increase in m. Furthermore, 20 fs oscillation of omega_p in the time domain indicates that the plasma-like edge is affected by the charge gap (0.2 eV) nature. Theoretical calculations suggest that the Coulomb repulsion plays an important role in the increase in m.