Events

R. G. Herb Condensed Matter Seminars

<< Fall 2022 Spring 2023 Summer 2023 >>
Subscribe your calendar or receive email announcements of events

Events During the Week of April 9th through April 16th, 2023

Monday, April 10th, 2023

No events scheduled

Tuesday, April 11th, 2023

No events scheduled

Wednesday, April 12th, 2023

No events scheduled

Thursday, April 13th, 2023

Valley and Momentum Polarization in Multilayer Graphene
Time: 10:00 am - 11:00 am
Place: 5310 Chamberlin
Speaker: Jia Leo Li, Brown University
Abstract: Within the flat energy bands of multilayer graphene, the enhanced influence of Coulomb interaction is reflected by the emergence of exchange-driven instabilities, which stabilize isospin-ordered phases by lifting the spin and valley degeneracy. These isospin-ordered phases are ubiquitous in the low-temperature phase space of multilayer graphene, having been observed in Bernal bilayer, rhombohedral trilayer, and a number of twisted graphene heterostructures near the magic-angle. Here, I will discuss a new type of Coulomb-driven instability that is driven by the exchange interaction between trigonal-warping-induced Fermi pockets. It is recently proposed that such instability could induce a spontaneous condensation of charge carriers into one of the Fermi pockets, giving rise to a net polarization in the momentum space. Such exchange-driven instability can be directly probed and characterized using angle-resolved nonlinear transport measurement at the second-harmonic frequency. Beyond the experimental identification of momentum polarization, I will discuss its implication on our understanding of electronic orders in the flat energy band of multilayer graphene.
Host: Alex Levchenko
Add this event to your calendar

Friday, April 14th, 2023

No events scheduled