Twist induced ferromagnetism in a bilayer graphene nanoflex

Twisted bilayer graphene shows various interesting phenomena like superconductivity, anomalous Hall effect, and ferromagnetism at a magic angle close to 1.1º. In this talk, we will discuss the observed ferromagnetism in a twisted bilayer graphene nanoflex (TBLGNF) using a first-principles approach. Our results demonstrate that when the energy gap of a TBLGNF approaches zero, electronic instability induced spontaneous reorganization of electrons leads to the emergence of a stable ferromagnetic gap state with p-orbitals at the boundary contributing to ferromagnetism [1]. We notice the ferromagnetic gap state appearing aperiodically between 0 and 30^o. A spin pairing mechanism is found to be responsible for the reappearance of the stable nonmagnetic phase when a ferromagnetic TBLGNF approaches an unstable metallic phase.