SPEAKER: Ramesh Budhani, Indian Institute of Technology, Kanpur, India
TITLE: Quantum Phases and Phase Transitions in Two-Dimensional Diffusive Metals at Oxide Interfaces
ABSTRACT: The two-dimensional diffusive metal stabilized at the interface of SrTiO3 and the Mott Insulator perovskite LaTiO3 1,2 has challenged many notions related to the formation and electronic behavior of the two dimensional electron gas at the well studies LaAlO3-SrTiO3 interface. Here we discuss specifically the stability of the superconducting phase3 at LaTiO3 – SrTiO3 interface, the nature of the superconductor – normal metal quantum phase transition (T=0 limit) driven by magnetic field, significance of the field vis-a-vis the Chandrasekhar - Clogston limit for depairing, and how the transition is initiated when the extent of Coulomb interaction amongst charge carriers is modulated by electrostatic gating4. The nature of the superconducting condensate is highlighted in the light of the Ti - t2g orbital driven bands and their filling in the presence of a strong Rashba spin – orbit interaction (SOI). Towards the end of the talk, we will also discuss the prominent effects of Rashba SOI on normal state quantum transport and how it renormalizes a Kondo-like electronic behavior in range of temperature Tc < T < 5 K5,6.