Finite-momentum pairing and topological aspects of superconductivity confined to interfaces

Date

Nov 5, 2014

Time

2:00 PM - 3:00 PM

Speaker

Florian Loder

Affiliation

Universität Augsburg

Language

en

Main Topic

Physik

Other Topics

Physik

Host

CMT seminars

Description

At the interface of certain insulating oxide materials, a quasi 2D layer of free electrons can form. Most well-known for this behavior is the interface between LaAlO3 and SrTiO3, where the interface enters a 2D superconducting state at low temperatures. Because of the broken inversion symmetry at the interface, the electrons forming the superconducting state are subject to a Rashba spin­orbit coupling (SOC). In this talk I will explore the unusual properties of this state emerging in the presence of a magnetic field. In the first part I will demonstrate the necessity to form electron pairs with a finite center­of­mass momentum if the magnetic field has a finite in­plane component, and characterize the possible pairing types. The second part concerns the possibility to drive the system into a topologically non­trivial superconducting state in a sufficiently strong magnetic field. While such a state was proposed for an out­of­plane magnetic field, I will argue that an experimental realization requires rather an in­plane magnetic field. In an in­plane field, the presence of finite­momentum pairing leads to a new and much richer phase diagram of topological states.

Last modified: Nov 5, 2014, 9:00:15 AM