Multifractally-enhanced superconductivity in thin films
arXiv:2101.12713 · doi:10.1016/j.aop.2021.168499
Abstract
The multifractal superconducting state originates from the interplay of Anderson localization and interaction effects. In this article we overview the recent theory of the superconductivity enhancement by multifractality and extend it to describe the spectral properties of superconductors on the scales of the order of the superconducting gap. Specifically, using the approach based on renormalization group within the nonlinear sigma model, we develop the theory of a multifractal superconducting state in thin films. We derive a modified Usadel equation that incorporates the interplay of disorder and interactions at energy scales larger than the spectral gap and study the effect of such an interplay on the low-energy physics. We determine the spectral gap at zero temperature which occurs to be proportional to the multifracally enhanced superconducting transition temperature. The modified Usadel equation results in the disorder-averaged density of states that, near the spectral gap, resembles the one obtained in the model of a spatially random superconducting order parameter. We reveal strong mesoscopic fluctuations of the local density of states in the superconducting state. Such strong mesoscopic fluctuations imply that the interval of energies in which the superconducting gap establishes is parametrically large in systems with multifractally-enhanced superconductivity.
arXiv comment30 pages, 3 figures, accepted to Localisation 2020 volume of Annals of Physics
References in corpus (20)
- Anderson Transitions
- Localization of preformed Cooper-pairs in disordered superconductors
- Disorder-Induced Inhomogeneities of the Superconducting State Close to the Superconductor-Insulator Transition
- Eigenfunction fractality and pseudogap state near superconductor-insulator transition
- Fractal superconductivity near localization threshold
- Pseudogap in a thin film of a conventional superconductor
- Quantum breakdown of superconductivity in low-dimensional materials
- Enhancement of superconductivity by Anderson localization
- Disorder induced multifractal superconductivity in monolayer niobium dichalcogenides
- Enhancing Superconductivity by Disorder
- Keldysh action for disordered superconductors
- Superconductivity in disordered thin films: giant mesoscopic fluctuations
- Multifractality at Anderson transitions with Coulomb interaction
- Universal Broadening of the Bardeen-Cooper-Schrieffer Coherence Peak of Disordered Superconducting Films
- Interaction-mediated surface state instability in disordered three-dimensional topological superconductors with spin SU(2) symmetry
- Keldysh Ginzburg-Landau action of fluctuating superconductors
- Subgap states in disordered superconductors
- Local density of states and its mesoscopic fluctuations near the transition to a superconducting state in disordered systems
- Nonlinear model for disordered superconductors
- Self-consistent-field ensembles of disordered Hamiltonians: Efficient solver and application to superconducting films
Cited by in corpus (18)
- The general approach to the critical phase with coupled quasiperiodic chains
- Nonlinear -model for disordered systems with intrinsic spin-orbit coupling
- Josephson effect in a Fibonacci quasicrystal
- Enhanced Amplitude for Superconductivity due to Spectrum-wide Wave Function Criticality in Quasiperiodic and Power-law Random Hopping Models
- Enhanced quantum metric due to vacancies in graphene
- Critical velocity of a two-dimensional superflow past a potential barrier of arbitrary penetrability
- Multifractally-enhanced superconductivity in two-dimensional systems with spin-orbit coupling
- Interplay of superconductivity and localization near a 2D ferromagnetic quantum critical point
- Generalized multifractality in the spin quantum Hall symmetry class with interaction
- Generalized surface multifractality in 2D disordered systems
- Local density of state fluctuations in 2D superconductor as a probe of quantum diffusion
- Enhancement of Superconductivity in a Dirty Marginal Fermi Liquid
- Boundary multifractality in the spin quantum Hall symmetry class with interaction
- Quantum Fluctuations and Multifractally-Enhanced Superconductivity in Disordered Thin Films
- Exploring the vortex phase diagram of Bogoliubov-de Gennes disordered superconductors
- Superconducting Diode Effect in Weak Localization Regime
- Multifractal correlations of the local density of states in dirty superconducting films
- Superfluid transition in quasi-two-dimensional disordered dipolar Fermi gases