Spontaneous emission properties of Pr ions located in planar dielectric microcavities

Spontaneous emission control around 490 nm for praseodymium ions implanted inside planar dielectric structures, such as microcavities, is investigated and compared with a theory. Using an Ar+ laser at 457.9 nm as the pump beam, we demonstrate the existence of an optimal pumping angle. Furthermore, we obtain enhanced and directive radiation patterns for the wavelength at which the cavities are tuned (490 nm) and underline very wavelength-dependent behavior of the patterns. In any case, good agreement is obtained between experiment and theory when we take the intrinsic Pr spectrum of emission into account independently of the structures' influence. (C) 1998 Optical Society of America.