Orateur
Description
Twisted trilayer graphene (TTG) has emerged as a particularly intriguing platform for studying moiré superconductivity. Its flat-band physics closely resembles that of twisted bilayer graphene, yet TTG offers an additional degree of tunability in its band structure, providing a valuable handle for uncovering the mechanisms of moiré superconductivity. In addition, the interference between the two moiré lattices in mirror-symmetry-broken TTG gives rise to a supermoiré lattice, introducing a new degree of freedom for exploring correlated electronic phenomena.
In the first part, we report the first transport observation of gate-tunable double-dome superconductivity in MATTG. We found that superconductivity is supressed near v=-2.6 in a small displacement field region. Through temperature, magnetic field and current bias dependence, we reveal the distinct transport behavior of the right and left dome superconductivities, as well as their corresponding normal states. In the second part, we report the existence of the supermoiré lattice in the mirror-symmetry-broken TTG, elucidating its role in generating mini flat bands and mini Dirac bands. We also demonstrate interaction-induced symmetry-broken phases in the supermoiré mini flat bands alongside the cascade of multiple superconductor-insulator transitions enabled by the supermoiré lattice.
Our work provides new insights into moiré graphene superconductivity and highlights the importance of the supermoiré lattice as an additional degree of freedom for tuning the electronic properties of twisted multilayer systems.