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

TL;DR

This paper investigates the effects of finite pulse durations in long-baseline quantum clock interferometry, analyzing how atomic center-of-mass delocalization influences experimental stability and precision.

Contribution

It develops a model for finite-time E1-M1 transitions considering atomic coupling and laser intensity variations, extending previous idealized models.

Findings

Quantum-clock interferometers are robust against optical field perturbations with small atomic delocalization.

Finite pulse effects can be modeled with atomic internal-external coupling and position-dependent laser intensities.

The stability of quantum-clock interferometry depends on controlling atomic delocalization and laser field variations.

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.