Writing and erasing topological defects in charge density wave materials with femtosecond laser pulses

Abstract

The ultrafast dynamics of charge density wave materials pumped by a series of femtosecond laser pulses has been investigated by numerically solving the time-dependent Ginzburg–Landau equation in (1+1) dimensions, where the topological defects can be written and erased repeatedly. The effects of laser fluence, light absorption length, relaxation time, phonon frequency, and coherence length on the number and locations of topological defects have also been studied extensively. The results here will not only be helpful to understand the rich dynamics of topological defects in optically excited charge density wave materials, but also have potential applications to develop optoelectronics devices by manipulating topological defects with femtosecond lasers.