Electronic Spectrum and Optical Properties of Quantum Wires Made from Transition Metal Dichalcogenides

The energy spectrum and optical absorption in a quantum wire of monolayer transition metal dichalcogenides in the shape of a straight strip are investigated theoretically. It is established that edge-like states with energies within the band gap of an infinite sample are absent in strips whose width is smaller than the critical one. Depending on the mutual parity of the quantum-confinement subbands in the valence and conduction bands, optical transitions are characterized by significantly differing threshold behaviors of the absorption strength. The strongest absorption corresponds to transitions between subbands with the same indices.