Emulating heavy fermions in twisted trilayer graphene

TL;DR

This paper proposes twisted trilayer graphene as a tunable platform to emulate heavy fermion physics, demonstrating control over localized and extended electronic modes and the transition between magnetic and heavy fermion regimes.

Contribution

It introduces twisted trilayer graphene as a new platform to realize and control heavy fermion physics through electronic structure manipulation and interlayer bias.

Findings

Localized modes lead to local moments in TTG

Electrical control can tune the system from magnetic to heavy fermion regimes

Potential realization of strongly correlated heavy fermion physics in carbon-based materials

Abstract

Twisted van der Waals materials have been shown to host a variety of tunable electronic structures. Here we put forward twisted trilayer graphene (TTG) as a platform to emulate heavy fermion physics. We demonstrate that TTG hosts extended and localized modes with an electronic structure that can be controlled by interlayer bias. In the presence of interactions, the existence of localized modes leads to the development of local moments, which are Kondo coupled to coexisting extended states. By electrically controlling the effective exchange between local moments, the system can be driven from a magnetic into a heavy fermion regime, passing through a quantum critical point. Our results put forward twisted graphene multilayers as a platform for the realization of strongly correlated heavy fermion physics in a purely carbon-based platform.