Condensed Matter Seminar

Friday 14 February 2020, 3:00pm to 4:00pm

Venue

Physics C36

Open to

Alumni, Postgraduates, Staff, Undergraduates

Registration

Registration not required - just turn up

Event Details

Cavity-mediated electron-photon superconductivity

Abstract: I will discuss how shaping the vacuum via a cavity can induce long-range attractive interactions between current fluctuations. These interactions can lead to pairing in generic materials with critical temperatures in the low-Kelvin regime for experimentally realistic parameters [1].

Specifically, I will investigate pairing in a two-dimensional electron system mediated by vacuum fluctuations inside a nanoplasmonic terahertz cavity. I will show that the induced state is a pair density wave superconductor which can show a transition from a fully gapped to a partially gapped phase - akin to the pseudogap phase in high-Tc superconductors. The long-range nature of the cavity induced interaction leads to a negligibly small energy penalty for a node in the pair wave function hence pushing singlet and triplet states close to degeneracy and may lead to topologically non-trivial phases [2]. Finally, I will discuss how an additional driving field may be utilized to gain control over the properties of the cavity induced interaction.

[1] F. Schlawin, A. Cavalleri and D. Jaksch, Cavity-mediated electron-photon superconductivity, Phys. Rev. Lett. 122, 133602 (2019).

[2] F. Schlawin and D. Jaksch, Cavity-mediated unconventional pairing in ultracold fermionic atoms, Phys. Rev. Lett. 123, 133601 (2019).

Contact Details

Name Dr Sergey Kafanov
Email

sergey.kafanov@lancaster.ac.uk