Non-London electrodynamics in a multiband London model : anisotropy-induced nonlocalities and multiple magnetic field penetration lengths
Silaev, M., Winyard, T., & Babaev, E. (2018). Non-London electrodynamics in a multiband London model : anisotropy-induced nonlocalities and multiple magnetic field penetration lengths. Physical Review B, 97(17), Article 174504. https://doi.org/10.1103/physrevb.97.174504
Published in
Physical Review BDate
2018Copyright
© 2018 American Physical Society
The London model describes strongly type-2 superconductors as massive vector field theories, where the
magnetic field decays exponentially at the length scale of the London penetration length. This also holds for
isotropic multiband extensions, where the presence of multiple bands merely renormalizes the London penetration
length. We show that, by contrast, the magnetic properties of anisotropic multiband London models are not this
simple, and the anisotropy leads to the interband phase differences becoming coupled to the magnetic field. This
results in the magnetic field in such systems having N + 1 penetration lengths, where N is the number of field
components or bands. That is, in a given direction, the magnetic field decay is described by N + 1 modes with
different amplitudes and different decay length scales. For certain anisotropies we obtain magnetic modes with
complex masses. That means that magnetic field decay is not described by a monotonic exponential increment set
by a real penetration length but instead is oscillating. Some of the penetration lengths are shown to diverge away
from the superconducting phase transition when the mass of the phase-difference mode vanishes. Finally the
anisotropy-driven hybridization of the London mode with the Leggett modes can provide an effectively nonlocal
magnetic response in the nominally local London model. Focusing on the two-component model, we discuss the
magnetic field inversion that results from the effective nonlocality, both near the surface of the superconductor
and around vortices. In the regime where the magnetic field decay becomes nonmonotonic, the multiband London
superconductor is shown to form weakly-bound states of vortices.
...
Publisher
American Physical SocietyISSN Search the Publication Forum
2469-9950Publication in research information system
https://converis.jyu.fi/converis/portal/detail/Publication/28040657
Metadata
Show full item recordCollections
License
Related items
Showing items with similar title or keywords.
-
Skyrmion formation due to unconventional magnetic modes in anisotropic multiband superconductors
Winyard, Thomas; Silaev, Mikhail; Babaev, Egor (American Physical Society, 2019)Multiband superconductors have a sufficient number of degrees of freedom to allow topological excitations characterized by skyrmionic topological invariants. In the most common, clean s -wave multiband systems, the ... -
Chirality selective spin interactions mediated by the moving superconducting condensate
Rabinovich, D. S.; Bobkova, I. V.; Bobkov, A. M.; Silaev, Mikhail (American Physical Society, 2018)We show that superconducting correlations in the presence of nonzero condensate velocity can mediate the peculiar interaction between localized spins that breaks the global inversion symmetry of magnetic moments. The proposed ... -
Polarization of the spontaneous magnetic field and magnetic fluctuations in s+is anisotropic multiband superconductors
Vadimov, V. L.; Silaev, Mikhail (American Physical Society, 2018)We show that multiband superconductors with broken time-reversal symmetry can produce spontaneous currents and magnetic fields in response to the local variations of pairing constants. Considering the iron pnictide ... -
Quasiclassical free energy of superconductors : Disorder-driven first-order phase transition in superconductor/ferromagnetic-insulator bilayers
Virtanen, Pauli; Vargunin, Artjom; Silaev, Mikhail (American Physical Society, 2020)n the seminal work by G. Eilenberger, Z. Phys. 214, 195 (1968), a closed-form expression for the free energy of inhomogeneous spin-singlet superconductor in terms of quasiclassical propagators has been suggested. However, ... -
Properties of dirty two-band superconductors with repulsive interband interaction: Normal modes, length scales, vortices, and magnetic response
Garaud, Julien; Corticelli, Alberto; Silaev, Mikhail; Babaev, Egor (American Physical Society, 2018)Disorder in two-band superconductors with repulsive interband interaction induces a frustrated competition between the phase-locking preferences of the various potential and kinetic terms. This frustrated interaction can ...