Optical properties and effect of magnetic field on energy spectra of a GaAs spherical quantum dot Vinod Kumar, S. B. Bhardwaj, Ram Mehar Singh and Fakir Chand Eur. Phys. J. Plus, 138 3 (2023) 191 Published online: 02 March 2023 DOI: 10.1140/epjp/s13360-023-03810-y