Dynamics of the superconducting order parameter through ultrafast normal-to-superconducting phase transition in Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ from multi-pulse polarization-resolved transient optical reflectivity

TL;DR

This study investigates the ultrafast dynamics of the superconducting order parameter in Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ using polarization-resolved transient optical reflectivity, revealing anisotropic gap recovery and comparing experimental results with theoretical models.

Contribution

It provides a detailed temperature-dependent analysis of the femtosecond optical response during the normal-to-superconducting transition in a cuprate superconductor, integrating experimental data with theoretical modeling.

Findings

Anisotropic superconducting gap recovery timescales at low temperatures.

Qualitative agreement between optical dynamics and TR-ARPES measurements.

Validation of phenomenological response functions with Ginzburg-Landau simulations.

Abstract

A systematic temperature dependent study of the femtosecond optical superconducting (SC) state destruction and recovery in Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ cuprate superconductor by means of the all-optical polarization-sensitive multi-pulse spectroscopy is presented. At low temperatures and a partial SC state suppression an anisotropic SC-gap recovery-timescale is suggested by the data. The SC state destruction and recovery dynamics are compared to the recent TR-ARPES-inferred SC-gap dynamics and a qualitative agreement is found. Using a phenomenological response function the experimental data are also compared to time dependent Ginzburg-Landau model simulations.