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arXiv · 2309.14426

Finite Pulse-Time Effects in Long-Baseline Quantum Clock Interferometry

Gregor Janson·Alexander Friedrich·Richard Lopp
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Abstract

Quantum-clock interferometry has been suggested as a quantum probe to test the universality of free fall (UFF) and the universality of gravitational redshift (UGR). In typical experimental schemes it seems advantageous to employ Doppler-free E1-M1 transitions which have so far been investigated in quantum gases at rest. Here, we consider the fully quantized atomic degrees of freedom and study the interplay of the quantum center-of-mass (COM) $-$ that can become delocalized $-$ together with the internal clock transitions. In particular, we derive a model for finite-time E1-M1 transitions with atomic intern-extern coupling and arbitrary position-dependent laser intensities. We further provide generalizations to the ideal expressions for perturbed recoilless clock pulses. Finally, we show at the example of a Gaussian laser beam that the proposed quantum-clock interferometers are stable against perturbations from varying optical fields for a sufficiently small quantum delocalization of the atomic COM.

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Gregor Janson, Alexander Friedrich, Richard Lopp. 2023-09-25. Finite Pulse-Time Effects in Long-Baseline Quantum Clock Interferometry. https://doi.org/10.1116/5.0178230

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