Growth and optical characterization of MoS2 single crystals with different dopants

Single crystals MoS2:X with different dopants X (X = Re, Nb, Fe, Co, Ni) were grown by the chemical vapor transport method using Br2 as transport agent. By analyzing the X-ray diffraction patterns, the structure of the single crystals shows rhombohedral symmetry for Re and Nb-doped and hexagonal symmetry for Fe, Co, and Ni-doped. Piezoreflectance (PzR) measurements along c-axis at 300 and 25 K were carried out to confirm the origin of the broad peak as observed in electrolyte electroreflectance (EER) measurements and check the optical quality of the samples. The energies and broadening parameters of the A and B excitons of the MoS2:X single crystals have been determined accurately.