  We report the significant enhancement on ultrafast terahertz optical
conductivity and the unexpected formation of a polaronic-like state in
semiconductor Mn3Si2Te6 at room temperature. With the absorption of pump
photons, the low-frequency terahertz photoconductivity spectrum exhibits a
significant rise, quickly forming a broad peak and subsequently shifting to
higher energy. The short-lived nature of the broad peak, as well as the
distribution of optical constants, strongly points towards a transient polaron
mechanism. Our study not only provides profound insights into the remarkable
photoelectric response of Mn3Si2Te6 but also highlights its significant
potential for future photoelectric applications.
