The oscillator algebra of Pegg--Barnett (P--B) oscillator with a finite-dimensional number-state space is considered. It is found that such a finite-dimensional oscillator possesses an su(n) Lie algebraic structure. A so-called supersymmetric P--B oscillator is suggested, and some related topics (such as the algebraic structure and the occupation number operator of the supersymmetric P--B oscillator) are briefly discussed. In addition, as one of the applications of the P--B quantization, a potential formula for the masses of charged leptons, which agrees reasonably well with the experimental values, is constructed based on the concept of supersymmetric P--B oscillator.

PACS numbers: 03.65.Fd, 02.20.Sv