تقرير
Mean-field theory of first-order quantum superconductor-insulator transition
| العنوان: | Mean-field theory of first-order quantum superconductor-insulator transition |
|---|---|
| المؤلفون: | Poboiko, Igor, Feigel'man, Mikhail |
| سنة النشر: | 2024 |
| المجموعة: | Condensed Matter |
| مصطلحات موضوعية: | Condensed Matter - Superconductivity, Condensed Matter - Disordered Systems and Neural Networks |
| الوصف: | Recent experimental studies on strongly disordered indium oxide films have revealed an unusual first-order quantum phase transition between the superconducting and insulating states (SIT). This transition is characterized by a discontinuous jump from non-zero to zero values of superfluid stiffness at the critical point, contradicting the conventional ``scaling scenario'' typically associated with SIT. In this paper, we present a theoretical framework for understanding this first-order transition. Our approach is based on the concept of competition between two fundamentally distinct ground states that arise from electron pairs initially localized by strong disorder: the superconducting state and the Coulomb glass insulator. These ground states are distinguished by two crucially different order parameters, suggesting a natural expectation of a discontinuous transition between them at $T=0$. This transition occurs when the magnitudes of the superconducting gap $\Delta$ and the Coulomb gap $E_C$ become comparable. Additionally, we extend our analysis to low non-zero temperatures and provide a mean-field ``phase diagram'' in the plane of $(T/\Delta,E_C/\Delta)$. Our results reveal the existence of a natural upper bound for the kinetic inductance of strongly disordered superconductors. Comment: 32 pages, 5 figures |
| نوع الوثيقة: | Working Paper |
| URL الوصول: | http://arxiv.org/abs/2405.08571 |
| رقم الأكسشن: | edsarx.2405.08571 |
| قاعدة البيانات: | arXiv |
| الوصف غير متاح. |