RESONANT FOCUSING IN A PLANAR MICROCAVITY

We study the focusing of a Gaussian laser beam in a microscopic planar cavity when the laser wavelength is resonant in the cavity but the be am divergence is larger than the acceptance angle of the cavity. Using the luminescence of implanted praseodymium ions as a microscopic prob e for the total electric field inside the spacer of the microresonator , we investigate theoretically and experimentally how strong focusing alters the photoexcitation of luminescent species located inside such a structure. (C) 1998 Optical Society of America [S0740-3224(98)00710- 3] OCIS codes: 180.2520, 310.6860, 260.3800.