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Technical limitations to homodyne detection at audio frequencies
Kirk McKenzie1, Malcolm B Gray, Ping Koy Lam
1Center for Gravitational Physics, Department of Physics, Faculty of Science, The Australian National University, ACT 0200, Australia. kirk.mckenzie@anu.edu.au
Applied Optics
|May 22, 2007
Summary
Homodyne detection, crucial for quantum optics and gravitational wave detectors, faces limitations from beam jitter, photodetector, and local oscillator intensity noise at audio frequencies.
Area of Science:
- Quantum Optics
- Gravitational Wave Detection
Background:
- Homodyne detection uses a local oscillator (LO) field beating with a signal beam for detection.
- This technique is vital for quantum optics and advanced gravitational wave interferometers.
Purpose of the Study:
- Investigate experimental limitations of homodyne detection at audio frequencies in a lab setting.
- Identify key noise sources impacting measurement precision.
Main Methods:
- Experimental setup for homodyne detection at audio frequencies.
- Analysis of noise contributions from beam jitter, photodetectors, and LO intensity.
Main Results:
- Beam jitter noise significantly impacts homodyne detection performance.
- Photodetector electronic noise and LO intensity noise are also critical limiting factors.
- Identified specific noise sources affecting homodyne detection in the audio frequency band.
Conclusions:
- Beam jitter, photodetector noise, and LO intensity noise limit audio-frequency homodyne detection.
- Understanding these limitations is crucial for improving advanced interferometric detectors.
- Potential solutions for mitigating these noise sources warrant further investigation.
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