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Spectral properties of high-gain parametric down-conversion.
K Yu Spasibko1, T Sh Iskhakov, M V Chekhova
1Department of Physics, M. V. Lomonosov Moscow State University, Leninskie Gory, 119992 Moscow, Russia.
Optics Express
|March 29, 2012
Summary
High-gain parametric down-conversion (PDC) produces bright squeezed vacuum, a quantum light state. This study observed a 27% spectral width increase in high-gain PDC, confirming theoretical predictions for quantum information applications.
Area of Science:
- Quantum Optics
- Nonlinear Optics
- Quantum Information Science
Background:
- Bright squeezed vacuum is a macroscopic nonclassical light state.
- Parametric down-conversion (PDC) is a key source for generating squeezed vacuum.
- High-gain PDC offers potential for advanced quantum information applications.
Purpose of the Study:
- Investigate the properties of high-gain parametric down-conversion (PDC).
- Characterize the spectral width and pairwise correlations of high-gain PDC output.
- Compare high-gain PDC properties with low-gain PDC.
Main Methods:
- Experimental generation of bright squeezed vacuum using high-gain PDC.
- Measurement of intensity spectral width.
- Analysis of frequency cross- and auto-correlations via noise reduction measurements.
Main Results:
- Observed a 27% increase in spectral width for high-gain PDC compared to low-gain PDC.
- Measured frequency cross- and auto-correlations by analyzing noise reduction in intensity differences.
- Demonstrated super-bunching behavior, consistent with collinear frequency-degenerate PDC.
Conclusions:
- High-gain PDC exhibits significantly broadened spectral properties.
- The observed spectral broadening and super-bunching are consistent with theoretical models.
- These findings validate high-gain PDC as a robust source for quantum information processing.
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