Ultrafast electronic dynamics in the metal-insulator transition compoundNdNiO3

Abstract

Visible ultrafast optical property studies have been performed in the metal-insulator transition compound $\mathrm{Nd}\mathrm{Ni}{\mathrm{O}}_3$ from room temperature down to $16\mathrm{K}$. A clear slowing down of the electronic relaxation is reported when the system becomes insulating. Two characteristic times of electronic relaxation have been found in the insulating phase while a single one is observed in the metallic state. Moreover, the magnitude of the ultrafast electronic transient reflectivity exhibits a drastic increase in the insulating state. Finally, a hysteresis of the electronic response is evidenced in accordance with electrical resistivity measurements.