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arXiv · 2408.10607

Generation of squeezed vacuum state in the millihertz frequency band

Li Gao·Li-ang Zheng·Bo Lu·Shaoping Shi·Long Tian·Yaohui Zheng
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Abstract

The detection of gravitational waves has ushered in a new era of observing the universe. Quantum resource advantages offer significant enhancements to the sensitivity of gravitational wave observatories. While squeezed states for ground-based gravitational wave detection have received marked attention, the generation of squeezed states suitable for mid-to-low-frequency detection has remained unexplored. To address the gap in squeezed state optical fields at ultra-low frequencies, we report on the first direct observation of a squeezed vacuum field until Fourier frequency of 4 millihertz with the quantum noise reduction of up to 8 dB, by the employment of a multiple noise suppression scheme. Our work provides quantum resources for future gravitational wave observatories, facilitating the development of quantum precision measurement.

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Li Gao, Li-ang Zheng, Bo Lu, Shaoping Shi, Long Tian, Yaohui Zheng. 2024-08-20. Generation of squeezed vacuum state in the millihertz frequency band. https://doi.org/10.1038/s41377-024-01606-y

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