# Optical Properties of SrMnO3n-LaMnO32n superlattices: an insulator-to-metal transition observed in the absence of disorder - Condensed Matter > Materials Science

Abstract: We measure the optical conductivity of SrMnO3n-LaMnO32n superlatticesSL for n=1,3,5, and 8 and 10 < T < 400 K. Data show a T-dependent insulatorto metal transition IMT for n \leq 3, driven by the softening of a polaronicmid-infrared band. At n = 5 that softening is incomplete, while at thelargest-period n=8 compound the MIR band is independent of T and the SL remainsinsulating. One can thus first observe the IMT in a manganite system in theabsence of the disorder due to chemical doping. Unsuccessful reconstruction ofthe SL optical properties from those of the original bulk materials suggeststhat SrMnO3n-LaMnO32n heterostructures give rise to a novel electronicstate.

Author: A. Perucchi, L. Baldassarre, A. Nucara, P. Calvani, C. Adamo, D.G. Schlom, P. Orgiani, L. Maritato, S. Lupi

Source: https://arxiv.org/