Abstract
The magneto-optic and optical properties of evaporated and sputtered Ag were studied experimentally and theoretically. An apparent Kerr effect near 3.9 eV was observed at room temperature. It was found to originate from the small off-diagonal term of dielectric function tensor,induced by the free electron movement under an applied magnetic field. The special optical properties near 3.9 eV due to the strong plasma absorption affect the line shape of the spectrum. The simulations,based on the classic Drude model,show the effective electron mass m* = 0.8m(0). This provides a new method to experimentally determine the effective electron mass and other parameters.