Multifunctional optoelectronic element based on n-InSe layered semiconductor doped with rare-earth elements

Abstract

The switching effect, the “phototrigger effect,” and electroluminescence were experimentally investigated in both pure and rare-earth (Ho and Er) doped n-InSe crystals. It was established that, under certain conditions, all three effects can be observed simultaneously in the same sample for both groups of crystals. For pure crystals, the parameters of these effects depend on the initial dark resistivity measured at 77 K. In contrast, for rare earth element (REE) doped crystals, the parameters do not depend on the chemical nature of the dopant but vary non-monotonically with its concentration (N_REE). The most stable characteristics were observed in pure crystals with the lowest initial specific dark resistivity, and in doped crystals with 10⁻²<N_REE<10⁻¹ at.%. The underlying physical mechanisms of these results are qualitatively discussed, and the potential applications of such effects in optoelectronic devices are highlighted.