Graphene multilayers: from unconventional superconductors to quantum devices

Time: Apr 16th, 10am – 11am

Location:  W M. Keck Computational Materials Theory Center Room 1310 – Live Oak

Speaker: Etienne Lantagne Hurtubise, Caltech (working with Jason Alicea and Gil Refael)

Title: Graphene multilayers: from unconventional superconductors to quantum devices

Abstract: 

Crystalline graphene multilayers present a rich playground to explore correlated electronic phenomena in a tunable and ultra-clean setting. For instance, Bernal bilayer graphene and rhombohedral trilayer graphene host multiple symmetry-broken metallic phases at low temperature, as well as unconventional superconductors with different pairing symmetries. The rich phase diagram of these systems can further be tuned through proximity to WSe2, which induces spin-orbit coupling in the graphene layers and leads to a dramatic enhancement of superconductivity that remains poorly understood. I will first discuss the lessons learned from our theoretical exploration of graphene multilayers with induced spin-orbit coupling, focusing on various types of magnetic and inter-valley coherent ground states and their possible connections to superconductivity. I will then outline a recipe to engineer topological superconductivity in graphene multilayers using gate-defined Josephson junctions. Such a platform provides a promising alternative to traditional architectures for Majorana zero-modes due to its purity, gate tunability and atomically thin nature.

About Speaker: 

For undergrad I studied in Montreal (Université de Montréal, graduated 2015), followed by a Master's degree at Perimeter Institute in Waterloo (2016) and Ph.D. with Marcel Franz at UBC (2021). Since then I am a Moore postdoc fellow at Caltech, working mostly with Jason and Gil.