Interaction-Assisted Spin Coherence in a Multimode Trapped Atomic Ensemble
Abstract
In a thermally occupied multimode trapped ensemble, mode-dependent detunings can strongly suppress Ramsey contrast even when the underlying dynamics remains coherent. We develop a weak-axis-resolved Hamiltonian theory in which collective mode spins experience longitudinal detunings and overlap-dependent exchange interactions. Without exchange, the distribution of detunings across thermally occupied modes produces coherent phase mixing and an algebraically decaying Ramsey-contrast envelope in the many-mode continuum regime. At the mean-field level, exchange generates a self-consistent restoring field that reduces phase dispersion and restores collective contrast. The crossover is governed by the competition between the collective exchange scale and the thermally induced detuning spread: when the late-time contrast is expressed in terms of their ratio, results at different temperatures collapse onto a common trend, and the crossover coupling follows the predicted inverse-square thermal scaling, with a numerical exponent of 2.06. Weak irreversible pure dephasing limits, but does not eliminate, this recovery, demonstrating that exchange refocuses coherent inhomogeneous phase mixing but cannot reverse irreversible phase noise.
Related
- Spatial coherence manipulation via the transient state in cascaded multimode-single-mode fibers
- Programmable high-dimensional state synthesis through a 20-m multimode fiber via long-coherence atomic photons
- A Cavity-Interfaced Register of Trapped-Ion Qubits with Multi-Second Coherence
- Canonical-ensemble scaling of Tan's contact in the trapped Tonks--Girardeau gas
- Reference-Beam-Assisted Perturbation-Resistant Imaging Through A Single Multimode Fiber
BibTeX
@misc{merabishvili2026interactionassisted,
title = {{Interaction-Assisted Spin Coherence in a Multimode Trapped Atomic Ensemble}},
author = {Aleksandre Merabishvili and Ebubechukwu O. Ilo-Okeke},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.09073},
eprint = {2610.09073},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.09073},
}
RIS
TY - UNPB
TI - Interaction-Assisted Spin Coherence in a Multimode Trapped Atomic Ensemble
AU - Aleksandre Merabishvili
AU - Ebubechukwu O. Ilo-Okeke
PY - 2026
DA - 2026/10/06
PB - arXiv
DO - 10.48550/arxiv.2610.09073
UR - https://arxiv.org/abs/2610.09073
AB - In a thermally occupied multimode trapped ensemble, mode-dependent detunings can strongly suppress Ramsey contrast even when the underlying dynamics remains coherent. We develop a weak-axis-resolved Hamiltonian theory in which collective mode spins experience longitudinal detunings and overlap-dependent exchange interactions. Without exchange, the distribution of detunings across thermally occupied modes produces coherent phase mixing and an algebraically decaying Ramsey-contrast envelope in the many-mode continuum regime. At the mean-field level, exchange generates a self-consistent restoring field that reduces phase dispersion and restores collective contrast. The crossover is governed by the competition between the collective exchange scale and the thermally induced detuning spread: when the late-time contrast is expressed in terms of their ratio, results at different temperatures collapse onto a common trend, and the crossover coupling follows the predicted inverse-square thermal scaling, with a numerical exponent of 2.06. Weak irreversible pure dephasing limits, but does not eliminate, this recovery, demonstrating that exchange refocuses coherent inhomogeneous phase mixing but cannot reverse irreversible phase noise.
ER -