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Microwave Photonics Systems Based on Whispering-gallery-mode Resonators
Published on: August 5, 2013
Low-threshold optical parametric oscillations in a whispering gallery mode resonator
J U Fürst1, D V Strekalov, D Elser
1Max Planck Institute for the Science of Light, Erlangen, Germany.
Physical Review Letters
|January 15, 2011
Summary
Whispering gallery mode resonators enable efficient optical frequency conversion. Researchers demonstrated a low-threshold optical parametric oscillator with a whispering gallery mode resonator, achieving a 6.7 μW threshold and sub-10 MHz linewidth.
Area of Science:
- Optics and Photonics
- Nonlinear Optics
- Quantum Optics
Background:
- Whispering gallery mode (WGM) resonators confine light via total internal reflection.
- Optically nonlinear materials enhance light-matter interactions in WGM resonators.
- High quality factors and small mode volumes are key for efficient optical frequency conversion.
Purpose of the Study:
- To analyze phase-matching conditions for optical parametric down-conversion (PDC) in spherical WGM resonators.
- To investigate the relationship between phase-matching and photon angular momentum sum rules.
- To demonstrate a low-threshold optical parametric oscillator (OPO) utilizing WGM resonators.
Main Methods:
- Theoretical analysis of phase-matching conditions in spherical WGM resonators.
- Experimental realization of an optical parametric oscillator (OPO) using lithium niobate.
- Characterization of the OPO's threshold, mode properties, and linewidth.
Main Results:
- Phase-matching conditions in WGM resonators directly relate to photon angular momentum sum rules.
- A very low parametric oscillation threshold is predicted and experimentally verified.
- A single-mode, strongly nondegenerate OPO was achieved with a threshold of 6.7 μW.
- The demonstrated OPO exhibited a linewidth under 10 MHz.
Conclusions:
- WGM resonators offer a highly efficient platform for optical parametric oscillation.
- The demonstrated OPO showcases the potential of WGM-based devices for frequency conversion.
- This work highlights the remarkable capabilities of whispering gallery mode resonators in nonlinear optics.
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