Researchers Develop Framework for Analyzing Noise Coupling in Space-Based Gravitational Wave Detectors
Physicists have established an analytical framework to systematically identify how laser and phase-modulation noise couple together in heterodyne interferometry systems used for gravitational wave detection. The work addresses previously unexplored noise interactions in space-based detectors like LISA, which relies on optical phase modulation for intersatellite clock synchronization. Understanding these noise couplings is critical for meeting the sensitivity requirements of next-generation gravitational wave observatories.
Researchers have developed a comprehensive analytical framework to systematically search for noise couplings in heterodyne interferometry systems used in space-based gravitational wave detectors such as the Laser Interferometer Space Antenna (LISA). The study addresses how phase modulation—necessary for intersatellite clock noise transfer—can cause various noise sources to couple into the final phase extraction process through a phasemeter. Beyond phase-modulation-induced noise, the framework also accounts for high-frequency laser phase noise. The analytical predictions were validated against numerical experiments, confirming the framework captures major noise coupling mechanisms. The researchers applied LISA-like parameters to derive specific requirements for acceptable laser and phase-modulation noise levels in high-frequency regimes, providing practical guidance for detector design.
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- arXiv physicsCenter
Searching systematically for coupling of laser and phase-modulation noise in heterodyne interferometry
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