Two-band superconductivity in doped SrTiO${}_3$ films and interfaces

Abstract

We investigate the possibility of multi-band superconductivity in SrTiO${}_3$ films and interfaces using a two-dimensional two-band model. In the undoped compound, one of the bands is occupied whereas the other is empty. As the chemical potential shifts due to doping by negative charge carriers or application of an electric field, the second band becomes occupied, giving rise to a strong enhancement of the transition temperature and a sharp feature in the gap functions, which is manifested in the local density of states spectrum. By comparing our results with tunneling experiments in Nb-doped SrTiO${}_3$, we find that intra-band pairing dominates over inter-band pairing, unlike other known multi-band superconductors. Given the similarities with the value of the transition temperature and with the band structure of LaAlO${}_3$/SrTiO${}_3$ heterostructures, we speculate that the superconductivity observed in SrTiO${}_3$ interfaces may be similar in nature to that of bulk SrTiO${}_3$, involving multiple bands with distinct electronic occupations.

revised expanded version

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Cited by in corpus (40)

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• Origin and Transport Signatures of Spin-Orbit Interactions in One- and Two-Dimensional SrTiO${}_3$-Based Heterostructures
• Superconductivity vs bound state formation in a two-band superconductor with small Fermi energy -- applications to Fe-pnictides/chalcogenides and doped SrTiO3
• Prospects and Applications Near Ferroelectric Quantum Phase Transitions
• Multi-band superconductivity and nanoscale inhomogeneity at oxide interfaces
• Unconventional multi-band superconductivity in bulk SrTiO${}_3$ and LaAlO${}_3$/SrTiO${}_3$ interfaces
• Multiorbital Ferroelectric Superconductivity in doped SrTiO3
• Superconductivity with Rashba Spin-Orbit Coupling and Magnetic Field
• Multiple nodeless superconducting gaps in optimally-doped SrTi${}_{1-x}$Nb${}_x$O${}_3$
• Multi-Orbital Superconductivity in SrTiO3 /LaAlO3 Interface and SrTiO3 Surface
• Modulation of the superconducting critical temperature due to quantum confinement at the LaAlO${}_3$/SrTiO${}_3$ interface
• Rise and fall of shape resonances in thin films of BCS superconductors
• BCS superconductivity near the band edge: Exact results for one and several bands
• Coexistence of giant Cooper pairs with a bosonic condensate and anomalous behavior of energy gaps in the BCS-BEC crossover of a two-band superfluid Fermi gas
• Quantum Critical Phenomena in a Compressible Displacive Ferroelectric
• Superconductivity from Orbital-Selective Electron-Phonon Coupling in $A{\mathrm{V}}_3{\mathrm{Sb}}_5$
• Upper critical field as a probe for multiband superconductivity in bulk and interfacial STO
• Inhomogeneous multi-carrier superconductivity at LaXO3/SrTiO3 (X=Al or Ti) oxide interfaces
• Gate-tunable hallmarks of unconventional superconductivity in non-centrosymmetric nanowires
• Evidence of incoherent carriers associated with resonant impurity levels and their influence on superconductivity in the anomalous superconductor Pb${}_{1-x}$Tl${}_x$Te
• Anomalous Josephson Coupling and High-Harmonics in Non-Centrosymmetric Superconductors with $S$-wave Spin-Triplet Pairing
• Competing superconducting phases in interacting two-dimensional electron gas with strong Rashba spin-orbit coupling
• Superconductivity in the vicinity of a ferroelectric quantum phase transition
• Post-quench gap dynamics of two-band superconductors
• Superconducting tunneling spectroscopy of spin-orbit coupling and orbital depairing in Nb:SrTiO${}_3$
• Impact of disorder on the superconducting transition temperature near a Lifshitz transition
• Tunable Coupling of Two-Dimensional Superconductors in Bilayer SrTiO3 Heterostructures
• Upper critical magnetic field and multiband superconductivity in artificial high-Tc superlattices of nano quantum wells
• Features of Excess Conductivity Behavior in a Magnetic Superconductor Dy${}_{0.6}$Y${}_{0.4}$Rh${}_{3.85}$Ru${}_{0.15}$B${}_4$
• Ferroelectricity-induced multiorbital odd-frequency superconductivity in SrTiO${}_3$
• Strain-induced superconductivity in Sr2IrO4
• Anomalous superconductivity and superfluidity in repulsive fermion systems
• Effects of paramagnetic pair-breaking and spin-orbital coupling on multi-band superconductivity
• Understanding the onset of negative electronic compressibility in one- and two-band 2D electron gases: Application to LaAlO${}_3$/SrTiO${}_3$
• Enhancing long-range order in disordered two-band s-wave superconductors
• High magnetic field response of superconductivity dome in quantum artificial High Tc superlattices with variable geometry
• Single-band to two-band superconductivity transition in two-dimensional oxide interfaces