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arXiv · 1802.08384

Quantum improved measurement of time transfer

Shaofeng Wang·Xiao Xiang·Nicolas Treps·Claude Fabre·Ruifang Dong·Tao Liu·Shougang Zhang
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Abstract

Accurate time transfer has become a crucial issue for future space experiments which require increasing resolution over large distances. In 2008, a scheme combining homodyne detection and mode-locked femtosecond lasers was proposed that leads to a potential timing precision reaching the yoctosecond range; with a multimode quantum frequency comb as the input field, the sub-shot noise measurement for the time transfer can further improve the timing precision. Based on this scheme and applying the multimode squeezing frequency comb that was measured to have a phase quadrature quantum noise reduction of 1.5 dB at the analyzing frequency 2MHz, the measurable timing fluctuation was reduced from a shot-noise limited value of 8.9E-23s to 7.5E-23s. To our knowledge, this is the first experimental demonstration of the time transfer measurement that achieves a precision beyond the standard quantum limit (SQL).

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Shaofeng Wang, Xiao Xiang, Nicolas Treps, Claude Fabre, Ruifang Dong, Tao Liu, Shougang Zhang. 2018-02-23. Quantum improved measurement of time transfer. https://doi.org/10.1103/physreva.98.053821

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