Diamagnetic shifts of free excitons in CuInS_2 in magnetic fields

摘要

Single crystals of CuInS_2 were studied with reflectance (RF) and photoluminescence (PL) at 4.2 K in magnetic fields up to 10 T. The diamagnetic energy shifts observed for the free excitonic lines in both the RF and PL spectra were used to calculate the reduced masses (0.141m_0, 0.142m_0, and 0.114m_0), binding energies (18.46, 18.59, and 14.90 meV), Bohr radii (3.82, 3.79, and 4.73 nm), and hole effective masses (1.20m_0, 1.28m_0, and 0.40m_0) for the A_(LPB), A_(UPB), and BC excitons, respectively, using a low-field perturbation approach.