Theory of superconductivity in doped quantum paraelectrics

Abstract

Recent experiments on Nb-doped SrTiO${}_3$ have shown that the superconducting energy gap to the transition temperature ratio maintains the Bardeen-Cooper-Schrieffer (BCS) value throughout its superconducting dome. Motivated by these and related studies, we show that the Cooper pairing mediated by a single soft transverse-optical phonon is the most natural mechanism for such a superconducting dome given experimental constraints, and present the microscopic theory for this pairing mechanism. Furthermore, we show that this mechanism is consistent with the $T^2$ resistivity in the normal state. Lastly, we discuss what physical insights SrTiO${}_3$ provides for superconductivity in other quantum paraelectrics such as KTaO${}_3$.

References in corpus (8)

• Theory of spin-orbit coupling at LaAlO3/SrTiO3 interfaces and SrTiO3 surfaces
• Two-dimensional superconductivity at the surfaces of KTaO3 gated with ionic liquid
• Electron-phonon interaction and charge carrier mass enhancement in SrTiO3
• Electric field control of disorder-tunable superconductivity and the emergence of quantum metal at an oxide interface
• Observation of two-dimensional superconductivity at the LaAlO3/KTaO3(110) heterointerface
• Origin of the large phonon band-gap in SrTiO3 and the vibrational signatures of ferroelectricity in ATiO3 perovskite: First principles lattice dynamics and inelastic neutron scattering of PbTiO3, BaTiO3 and SrTiO3
• Intrinsic Mobility Limiting Mechanisms in Lanthanum-doped Strontium Titanate
• Phonon mediated superconductivity in low carrier-density systems

Cited by in corpus (11)

• Tunable superconductivity at the oxide-insulator/KTaO${}_3$ interface and its origin
• Generalized Rashba Electron-Phonon Coupling and Superconductivity in Strontium Titanate
• A theory of criticality for quantum ferroelectric metals
• Revealing subterahertz atomic vibrations in quantum paraelectrics by surface-sensitive spintronic terahertz spectroscopy
• Beyond being free: glassy dynamics of SrTiO${}_3$-based two-dimensional electron gas
• Modeling polar order in compressively strained SrTiO${}_3$
• Electronic spin susceptibility in metallic strontium titanate
• Effects of Homogeneous Doping on Electron-Phonon Coupling in SrTiO3
• Spin-dependent anisotropic electron-phonon coupling in KTaO${}_3$
• Phonon-mediated spin transport in quantum paraelectric metals
• Effects of doping on polar order in SrTiO${}_3$ from first-principles modeling