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Phase correlation of laser waves with arbitrary frequency spacing
A F Huss1, R Lammegger, C Neureiter
1Institut für Experimentalphysik, Technische Universität Graz, Petersgasse 16, 8010 Graz, Austria.
Physical Review Letters
|December 17, 2004
Summary
Laser phase fluctuations are experimentally correlated in Lambda-type schemes. A double-Lambda scheme extends this correlation to all noise frequencies, enabling GHz-level frequency difference measurements.
Area of Science:
- Quantum optics
- Laser physics
Background:
- Laser phase fluctuations can impact the precision of optical measurements.
- Lambda-type and double-Lambda schemes are used in atomic and quantum optics for light-matter interactions.
Purpose of the Study:
- To experimentally demonstrate the correlation of laser phase fluctuations in Lambda-type schemes.
- To investigate the frequency dependence of this correlation mechanism.
- To explore the potential of double-Lambda schemes for correlating electromagnetic fields with large frequency differences.
Main Methods:
- Experimental demonstration of laser phase fluctuation correlation.
- Utilizing Lambda-type and double-Lambda atomic interaction schemes.
- Analysis of correlation behavior across different noise frequencies.
Main Results:
- Correlation of laser phase fluctuations is confirmed in Lambda-type schemes.
- The correlation mechanism in Lambda schemes is limited to high-frequency noise.
- In double-Lambda schemes, correlation extends to all noise frequencies due to laser phase locking.
- The double-Lambda scheme shows weak sensitivity to coherence losses.
Conclusions:
- The double-Lambda scheme effectively correlates laser phase fluctuations across all noise frequencies.
- This scheme enables the correlation of electromagnetic fields with carrier frequency differences exceeding the GHz range.
- The robustness to coherence losses makes the double-Lambda scheme a promising tool for advanced optical applications.
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