Acta Optica Sinica, Vol. 34, Issue 2, 223001 (2014)

Cavity Quantum Electrodynamic Fluorescence Enhancement Effect of Nd³⁺-Doped Chalcogenide Glass Microspheres

Abstract

Homemade Nd3+ doped chalcogenide glass microspheres are fabricated using the method of melting floating glass powder at high temperature. It is reported that the fluorescence spectra of chalcogenide glass microsphere are modified by the cavity quantum electrodynamic enhancement effect. A 90.53-μm diameter chalcogenide glass microsphere is coupled with the silica fiber-taper that has a cross-sectional diameter of 1.02 μm. An 808-nm laser is used as a pumping source for the microsphere cavity and separate resonance peaks found in the microsphere fluorescence spectra. According to the Mie scattering theory, positions and mode ordinals of three resonance peaks for the fundamental TE mode are calculated. Based on the formula for calculating the cavity quantum electrodynamic enhancement factor, it is found that the enhancement factor η of our chalcogenide glass microsphere is 1122, which indicates that spontaneous fluorescence emission rate is enhanced by 1122 times. By simplifying the enhancement factor formula for the fundamental TE mode, it is found that the enhancement factor estimated is 1167, which indicates an error rate of 4%.

keywords

• cavity quantum electrodynamics
• chalcogenide glass
• microsphere
• Mie scattering theory
• optical devices
• whispering gallery mode