Andrea Young
UCSB
In this talk I will introduce the electronic structure of rhombohedral trilayer graphene, which hosts a saddle point van Hove singularity. Experiments probing thermodynamic density of states and electronic transport show that as the density is tuned towards the van Hove singularity, a cascade of ferromagnetic transitions occurs between states with broken spin and/or valley symmetries, including “half-metal” and “quarter-metal” states with a variety of Fermi surface topologies. Unexpectedly, we find superconducting states in the proximity of several of these magnetic transitions, including one superconducting state that emerges from a spin polarized half metal. I will review possible origins for these superconducting states.
References:
Zhou et al., arXiv:2106.07640
Zhou et al., arXiv:2104.00653