Optical absorption in molybdenum disulfide nanotubes

Symmetry based calculations of the polarized optical absorption in single-wall MoS2 nanotubes are presented. Optical conductivity tensor for the individual tubes, using line group symmetry implemented POLSym code and DFTB-calculated Slater type orbital functions and Hamiltonian/overlap matrix elements as input data is numerically evaluated. This minimal, full symmetry implementing algorithm enabled calculations of the optical response functions very efficiently and addressing the large diameter tubes and highly chiral tubes (which have huge number of atoms within a unit cell) as well. The absorption spectra dependence on the diameter and chiral angle of the nanotubes is investigated. The results obtained are related to the previously reported measured spectra.