Tunable Optical Excitations in Twisted Bilayer Graphene Form Strongly Bound Excitons
Tunable Optical Excitations in Twisted Bilayer Graphene Form Strongly Bound Excitons
When two sheets of graphene stack in a twisted bilayer graphene (tBLG) configuration, the resulting constrained overlap between interplanar 2p orbitals produce angle-tunable electronic absorption resonances. By applying a novel combination of multiphoton transient absorption (TA) microscopy and TEM, we resolve the electronic structure and ensuing relaxation by probing resonant …