Instanton theory and fluctuation corrections to the thermal nucleation rate of a ferromagnetic superfluid
Fuente:
arXiv
Saved in:
| Main Authors: | , |
|---|---|
| Format: | Preprint |
| Published: |
2025
|
| Subjects: | |
| Online Access: | |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1866912816918691840 |
|---|---|
| author | Garcia, Enrique Rozas Hofmann, Johannes |
| author_facet | Garcia, Enrique Rozas Hofmann, Johannes |
| contents | We provide a field-theoretical description of thermal nucleation in a one-dimensional ferromagnetic superfluid, a quantum-gas analogue of false-vacuum decay. The rate at which ground-state domains nucleate follows an Arrhenius law, with an exponential factor determined by a saddle-point of the energy functional -- the critical droplet or instanton -- and a magnitude fixed by small fluctuations about this configuration. We evaluate both contributions over the full parameter space, using a Gel'fand-Yaglom approach to reduce the calculation of the fluctuation spectrum to an initial-value problem. In addition, we obtain a closed-form expression for critical droplets close to the coexistence line, and use it to formulate an effective theory of domain nucleation and growth as a Kramers escape problem for the droplet size. Our results determine the parametric dependence of the nucleation rate and predict its signature in experimental images of a nucleating gas, increasing the rigor of comparisons between nucleation theory and experiment. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2512_20734 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Instanton theory and fluctuation corrections to the thermal nucleation rate of a ferromagnetic superfluid Garcia, Enrique Rozas Hofmann, Johannes Quantum Gases Statistical Mechanics We provide a field-theoretical description of thermal nucleation in a one-dimensional ferromagnetic superfluid, a quantum-gas analogue of false-vacuum decay. The rate at which ground-state domains nucleate follows an Arrhenius law, with an exponential factor determined by a saddle-point of the energy functional -- the critical droplet or instanton -- and a magnitude fixed by small fluctuations about this configuration. We evaluate both contributions over the full parameter space, using a Gel'fand-Yaglom approach to reduce the calculation of the fluctuation spectrum to an initial-value problem. In addition, we obtain a closed-form expression for critical droplets close to the coexistence line, and use it to formulate an effective theory of domain nucleation and growth as a Kramers escape problem for the droplet size. Our results determine the parametric dependence of the nucleation rate and predict its signature in experimental images of a nucleating gas, increasing the rigor of comparisons between nucleation theory and experiment. |
| title | Instanton theory and fluctuation corrections to the thermal nucleation rate of a ferromagnetic superfluid |
| topic | Quantum Gases Statistical Mechanics |
| url | https://arxiv.org/abs/2512.20734 |