Anisotropic electrolyte electroreflectance study of rhenium-doped MoS₂

Abstract

Anisotropy of rhenium-doped MoS2 parallel and perpendicular to the c-axis (k∥c and k⊥c) was studied using electrolyte electroreflectance (EER) measurements over an energy range from 1.75 eV to 4.5 eV. The measurements for k⊥c were made possible by the thicker samples of MoS2 available through introducing a small concentration of rhenium during growth. The excitonic transitions A and B for both k⊥c and k∥c configurations showed different degrees of red shift compared with that of the undoped sample. It is found that rhenium which is present as an intentionally doped impurity plays an important role in affecting the observed differences.