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تسجيل مستخدم جديدMethod of Power Recycling in Co-Axial Mach Zender Interferometers for Low Noise Measurements
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We present the first experimental study of a new type of power recycling microwave interferometer designed for low noise measurements. This system enhances sensitivity to phase fluctuations in a Device Under Test, independent of input power levels. The single sideband thermal white phase noise floor of the system has been lowered by 8 dB (reaching -185 dBc/Hz at 1 kHz offset frequency) at relatively low power levels (13 dBm).
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The sensitivity of current and planned gravitational wave interferometric detectors is limited, in the most critical frequency region around 100 Hz, by a combination of quantum noise and thermal noise. The latter is dominated by Brownian noise: therm
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