Excited-state dynamics of structurally characterized crystal of SnxSb1-x

TL;DR

This study investigates the ultrafast excited-state dynamics of SnxSb1-x crystals, revealing band filling phenomena and power-dependent charge carrier behavior, with implications for nonlinear optical applications.

Contribution

It provides detailed transient reflectance measurements of SnxSb1-x alloys, highlighting their nonlinear optical properties and bandgap variations under excitation.

Findings

Negative differential reflectance observed

Charge carrier increase with power

Bandgap values estimated from transient data

Abstract

The topological behavior of heavy metal alloys opens a vast area for incredible research and future technology. Here, we extend our previous report about the superconducting properties of Sn0.4Sb0.6 along with the compositional variation of Sn and Sb in SnxSb1-x (with (X=0.5 and 0.6)) to study the detailed optical properties. Structural and morphological details of grown crystal are carried from the previous study. Further, the samples are excited by a pump of 2.61 eV with a broad probe of 0.77-1.54 eV in the NIR regime for transient reflectance ultrafast studies (TRUS) measurements. The differential reflectance profile shows an unprecedented negative magnitude, and the average power-dependent analysis of this negative trend has been analyzed. This article not only provides evidence of band filling phenomenon in the samples but also shows that with the variation of average power, there is a definite increase in the excited charge carriers, and thereby enhancing the band filling response. The estimated value of the bandgap between the band filled states and valence state is also determined from these studies. The nonlinear properties and bandgap analysis of the studied topological alloys and similar materials help in the advancement of various nonlinear optical applications.