IEEE Photonics Technology Letters

Design of Rare-Earth-Doped Microspheres

Luciano Mescia, Francesco Prudenzano, M. De Sario, Tommaso Palmisano, Maurizio Ferrari, Giancarlo Cesare Righini

Published Jan 20, 2010• 16 citations

Abstract

Two original computer codes for the design of rare-earth-doped dielectric microspheres have been ad hoc developed. The former code is based on a finite-difference time-domain algorithm, suitably extended to model the amplification of the whispering-gallery modes propagating into rare-earth-doped microspheres. It takes into account the wavelength dispersion of the microsphere refractive index and the polarization obtained via the density matrix model. The design of an Er3+-doped silica microsphere coupled with a tapered silica fiber is reported. The latter home-made computer code solves the rate equations and the power propagation equations in frequency domain. The results are in excellent agreement.

DOI: 10.1109/lpt.2009.2039932

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