Saved in:
| Main Authors: | , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | https://arxiv.org/abs/2505.02112 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866909600999014400 |
|---|---|
| author | Cheng, Changhao Guo, Jinxian |
| author_facet | Cheng, Changhao Guo, Jinxian |
| contents | The pursuit of high optical depth and long coherence time in atomic ensembles faces a fundamental thermodynamic constraint: heating enhances light-atom coupling via increased density but degrades coherence through thermal broadening, while laser cooling preserves coherence at the cost of density loss. Here, we demonstrate a non-equilibrium strategy that spatially achieves a negative correlation between density and temperature via controlled thermal-gradient transport. By engineering a temperature gradient via laser-cooling in a hot vapor cell, we drive a convective atomic fluid that expels hot atoms at the boundary while confining low-temperature atoms in the central region. This dynamic process sustains a density of 10^22m^-3 and a temperature of tens of kelvins at the center. A theoretical scheme based on the Boltzmann-type transport equation is established, which gives Navier-Stokes equations for non-equilibrium thermal-gradient atomic fluid. The results of numerical simulation indicate that this scheme can enhance the optical depth while reducing the temperature of the system, establishing a route to bypass equilibrium thermodynamics in room-temperature atom-light interactions, boosting high-performance quantum metrology and quantum information applications. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2505_02112 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Thermal-Gradient Cooling of Atomic Vapor Fluid Cheng, Changhao Guo, Jinxian Atomic Physics The pursuit of high optical depth and long coherence time in atomic ensembles faces a fundamental thermodynamic constraint: heating enhances light-atom coupling via increased density but degrades coherence through thermal broadening, while laser cooling preserves coherence at the cost of density loss. Here, we demonstrate a non-equilibrium strategy that spatially achieves a negative correlation between density and temperature via controlled thermal-gradient transport. By engineering a temperature gradient via laser-cooling in a hot vapor cell, we drive a convective atomic fluid that expels hot atoms at the boundary while confining low-temperature atoms in the central region. This dynamic process sustains a density of 10^22m^-3 and a temperature of tens of kelvins at the center. A theoretical scheme based on the Boltzmann-type transport equation is established, which gives Navier-Stokes equations for non-equilibrium thermal-gradient atomic fluid. The results of numerical simulation indicate that this scheme can enhance the optical depth while reducing the temperature of the system, establishing a route to bypass equilibrium thermodynamics in room-temperature atom-light interactions, boosting high-performance quantum metrology and quantum information applications. |
| title | Thermal-Gradient Cooling of Atomic Vapor Fluid |
| topic | Atomic Physics |
| url | https://arxiv.org/abs/2505.02112 |