Bulk and surface optical absorption in molybdenum disulfide

Abstract

Optical absorption in crystalline MoS2 has been measured from 0.7 to 3.5 eV using photothermal deflection and transmission spectroscopies. We have determined the indirect band gap in both natural and synthetic material. Photon energies below the band gap show defect absorption which is strongly concentrated at the edge surfaces. These surface defects have the same optical properties in microcrystals and lithographically textured single crystals.