Yu-Shiba-Rusinov states in real metals

Abstract

Theoretical descriptions of Yu-Shiba-Rusinov (YSR) states induced by magnetic impurities inside the gap of a superconductor typically rely on a classical spin model or are restricted to spin-1/2 quantum spins. These models fail to account for important aspects of YSR states induced by transition-metal impurities, including the effects of higher quantum spins coupled to several conduction-electron channels, crystal or ligand-field effects, and magnetic anisotropy. We introduce and explore a zero-bandwidth model, which incorporates these aspects, is readily solved numerically, and analytically tractable in several limiting cases. The principal simplification of the model is to neglect Kondo renormalizations of the exchange couplings between impurity spin and conduction electrons. Nevertheless, we find excellent correspondence in those cases, in which we can compare our results to existing numerical-renormalization-group calculations. We apply the model to obtain and understand phase diagrams as a function of pairing strength and magnetic anisotropy as well as subgap excitation spectra. The single-channel case is most relevant for transition-metal impurities embedded into metallic coordination complexes on superconducting substrates, while the multi-channel case models transition-metal adatoms.

23 pages, 10 figures, to appear in Phys. Rev. B

References in corpus (23)

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• Distinguishing a Majorana zero mode using spin resolved measurements
• Spectral properties of locally correlated electrons in a BCS superconductor
• Topological Superconductivity induced by Ferromagnetic Metal Chains
• Strong localization of Majorana end states in chains of magnetic adatoms
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• Orbital Picture of Yu-Shiba-Rusinov Multiplets
• Properties of anisotropic magnetic impurities on surfaces
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• Kondo effect in asymmetric Josephson couplings through a quantum dot
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• Controlling in-gap end states by linking nonmagnetic atoms and artificially-constructed spin chains on superconductors
• Observation of magnetic adatom-induced Majorana vortex and its hybridization with field-induced Majorana vortex in an iron-based superconductor
• Phase diagram and excitations of a Shiba molecule
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Cited by in corpus (33)

• Quantum spins and hybridization in artificially-constructed chains of magnetic adatoms on a superconductor
• Yu-Shiba-Rusinov qubit
• Quantum magnetism and topological superconductivity in Yu-Shiba-Rusinov chains
• Pair excitations of a quantum spin on a proximitized superconductor
• Quantum Yu-Shiba-Rusinov dimers
• Zeeman effects on Yu-Shiba-Rusinov states
• Engineering anomalous Floquet Majorana modes and their time evolution in helical Shiba chain
• Inductive microwave response of Yu-Shiba-Rusinov states
• Tailoring phase transition from topological superconductor to trivial superconductor induced by magnetic textures of a spin-chain on a $p$-wave superconductor
• Calculations of in-gap states of ferromagnetic spin chains on \textit{s}-wave wide-band superconductors
• Quasiparticle focusing of bound states in two-dimensional $s$-wave superconductors
• Tracking a Spin-Polarized Superconducting Bound State across a Quantum Phase Transition
• Double-quantum-dot Andreev molecules: Phase diagrams and critical evaluation of effective models
• Impurity-induced excitations in a topological two-dimensional ferromagnet/superconductor van der Waals moiré heterostructure
• Theory of a Single Magnetic Impurity on a Thin Metal Film in Proximity to a Superconductor
• Quantum spin driven Yu-Shiba-Rusinov multiplets and fermion-parity-preserving phase transition in K${}_3$C${}_{60}$
• Tunneling spectra of impurity states in unconventional superconductors
• Probing Magnetic and Triplet Correlations in Spin-Split Superconductors with Magnetic Impurities
• Magnetic impurities on superconducting Pb surfaces
• Robust Spin Polarization of Yu-Shiba-Rusinov States in Superconductor/Ferromagnetic Insulator Heterostructures
• Quantifying the quantum nature of high spin YSR excitations in transverse magnetic field
• Diluted Yu-Shiba-Rusinov arrays on the $\beta$-Bi${}_2$Pd anisotropic superconductor
• Yu-Shiba-Rusinov states, the BCS-BEC crossover, and the exact solution in the flat-band limit
• Spectral properties of fractionalized Shiba states
• Preparation and readout of Majorana qubits in magnet-superconductor hybrid systems
• Anomalous Shiba spectrum and superconductivity induced magnetic interactions in materials with topological band inversion
• Odd-parity ground state in dilute Yu-Shiba-Rusinov dimers and chains
• Kondo Screening and Indirect Magnetic Exchange through a Conventional Superconductor Studied by the Density-Matrix Renormalization Group
• A Large-$N$ Approach to Magnetic Impurities in Superconductors
• A minimal model of inelastic tunneling of vibrating magnetic molecules on superconducting substrates
• Density-functional description of materials for topological qubits and superconducting spintronics
• Yu-Shiba-Rusinov States in Ising Superconductors
• Yu-Shiba-Rusinov multiplets and clusters of multiorbital adatoms in superconducting substrates: Subgap Green's function approach