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Characterizing Far-infrared Laser Emissions and the Measurement of Their Frequencies
Published on: December 18, 2015
Temporal coherence of laser fields analyzed by heterodyne interferometry
Applied Optics
|April 8, 2010
Summary
A new method quantifies coherence in partially coherent fields, revealing microphonic noise as a key factor in laser incoherence. Experiments show even uncorrelated fields can exhibit strong phase relationships.
Area of Science:
- Optics and Photonics
- Statistical Physics
Background:
- Partially coherent fields are crucial in various optical applications.
- Understanding coherence properties is essential for advanced optical systems.
- Existing methods for characterizing coherence can be limited, especially for large coherence times.
Purpose of the Study:
- To introduce a novel method for determining the coherence function and statistical properties of partially coherent fields.
- To investigate the dominant sources of incoherence in laser fields.
- To explore phase relationships in seemingly uncorrelated optical fields.
Main Methods:
- Development of a new technique to measure coherence properties.
- Experimental measurement of coherence lengths.
- Analysis of noise sources contributing to field incoherence.
Main Results:
- Coherence lengths exceeding 100 meters were successfully measured.
- Microphonic noise was identified as the primary cause of incoherence in laser fields.
- Experimental evidence demonstrated strong phase relationships in fields previously considered uncorrelated.
Conclusions:
- The new method effectively characterizes coherence in partially coherent fields.
- Mitigating microphonic noise is critical for maintaining laser field coherence.
- The findings challenge assumptions about phase relationships in optical fields.
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