Ring-Type Erbium-Doped Antiresonant Reflecting Optical Waveguide Amplifier Analysis and Design

Abstract

Erbium-doped antiresonant reflecting optical wave-1 guides (ARROWs) allow combining wavelength selective guiding 2 due to their attractive spectral versatility with an active opera-3 tion. In this letter, the analysis and design of a ring-type erbium-4 doped ARROW amplifier is presented. The influence of the 5 involved passive and active parameters (ring thickness and diam-6 eter, refractive index variation, pump and signal wavelengths, 7 Er 3+ -ion concentration, and input pump power) on the spectral 8 response of the structure and the optical power propagation losses 9 and on the amplifier performance is numerically analysed. The 10 opposite influence of the ring diameter on the optical power 11 confinement and on the pump power density causes the existence 12 of a diameter value that maximizes the amplifier net gain. For a 13 cladding refractive index of 1.4 and moderate index variations, 14 n = 0.2 − 0.4, the optimum ring diameter is in the range 15 of 20 μm. To compensate signal confinement losses (a few dB/cm), 16 high erbium concentrations (∼1 × 10 26 ion/m 3 ) are required. 17 Index Terms-ARROW, Er 3+ -doping, optical amplifier, opti-18 mized design.19