High temperature superconductivity in semiconductor artificial graphene

Speaker: Julian Ingham, Boston University, Physics Department

When: October 16, 2019 (Wed), 03:30PM to 04:30PM (add to my calendar)
Location: SCI 328

This event is part of the Condensed Matter Theory Seminar Series.

Semiconductor artificial graphene (AG) seeks to replicate the properties of graphene, by subjecting a two-dimensional electron gas to a periodic potential with the same symmetries as the atomic lattice in graphene. In this talk I will explain how this material can realise a new mechanism for high temperature superconductivity — due to the antiscreened fluctuations of the emergent pseudospin degree of freedom. The mechanism originates solely from the repulsive Coulomb interaction, and relies on the Dirac dispersion and a strong periodic potential — and could therefore in principle be realised in other Dirac materials. The ability to artificially tune the lattice spacing, potential strength and density in AG allows this regime to be engineered, and the calculations I present show that Tc can be order 25 K for realistic experimental parameters.