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Hot-spots and gain enhancement in a doubly pumped parametric down-conversion process.
Optics Express
|December 31, 2020
Summary
Researchers observed bright hot-spots in nonlinear bulk crystals, mimicking 2D photonic crystals. This phenomenon enables the creation of complex entangled light states using simple bulk sources.
Area of Science:
- Nonlinear optics
- Quantum optics
- Condensed matter physics
Background:
- Parametric down-conversion is a key process for generating quantum light states.
- Previous studies observed similar phenomena in 2D nonlinear photonic crystals.
Purpose of the Study:
- To experimentally investigate parametric down-conversion in nonlinear bulk crystals.
- To explore the generation of multimode entangled states of light.
Main Methods:
- Utilizing two non-collinear pump modes to drive the parametric down-conversion.
- Exploiting spatial walk-off between extraordinary pump modes to induce resonance.
Main Results:
- Observed bright hot-spots in shared modes, analogous to 2D photonic crystals.
- Identified a resonance condition enhancing parametric gain.
- Demonstrated a transition from three-mode to four-mode coupling.
Conclusions:
- This work demonstrates a method for generating multimode entangled states in bulk nonlinear sources.
- The findings pave the way for creating tripartite and quadripartite entangled states.
- The study bridges observations in 2D photonic crystals with bulk nonlinear optics.
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