Magnetoabsorption spectra of band-edge excitons in 2H-PbI2at high magnetic fields up to 40 T

Magnetoabsorption spectra of band-edge exciton series in 2H-${\mathrm{PbI}}_2$ single crystals are measured up to 40 T with a configuration of E⊥c∥B. This is the first observation of energy splittings and shifts of the three distinct exciton lines as a function of applied magnetic field. From the linear Zeeman splitting and diamagnetic shift of the ground-state absorption line, an effective g value is estimated as $g_{\perp }$=0.89 and the binding energy as 63 meV. The binding energy of the ground-state exciton is much smaller than the value in the model of Harbeke and Tosatti [J. Phys. Chem. Solids 37, 126 (1976)].