Marcin Bober, Michal Zawada
Proceedings Volume Emerging Imaging and Sensing Technologies for Security and Defence II, 104380H https://doi.org/10.1117/12.2277402
Optical atomic clocks are the most precise measurements ever build by the mankind. Accuracy at the level of 10^-18 [1,2] and instability in mid 10^-17 after 1 s of averaging [3] was already presented. With all perturbation under control one can use a clock not only for precise time measurements but also for other physical quantity measurements, e.g. for looking for fundamental constants variations [4] or dark matter in form of topological defects [5]. Atomic clocks are also directly sensitive to the gravitational potential, i.e. they can be used as a gravitational waves detectors [6] and in relativistic geodesy [7,8].
All modern optical atomic clocks are passive, with an oscillator in the form of ultra-stable laser and a frequency discriminator in the form of cold atomic sample. We would like to propose instead an active optical atomic clock [9] as a gravitational detector. Such an active frequency standard would take advantage form both better instability and higher time resolution over already existing optical clocks. Its construction will provide a high degree of mobility, since its performance would not be limited by an instability of a fragile optical cavity.
We will present potential advantages of using active optical clocks as gravitational potential detectors along with gravimeters measuring acceleration. A combination of both devices can remotely detects not only small gravitational anomalies or objects, but also precisely locate them. Moreover, shape and mass distribution can also be derived.
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