Physics

Metric (unit)

Cooper pair

Hubbard model

Pairing

Economics

Superfluidity

Operations management

Condensed matter physics

Superconductivity

Quantum mechanics

Physical review. B./Physical review. B

Flat band systems such as twisted bilayer graphene superconduct thanks to nontrivial band wave functions. The work here relates the superfluid weight and the Cooper pair mass in isolated flat bands to the new concept of minimal quantum metric, solving an underappreciated, yet crucial issue in previous work. Moreover, the authors demonstrate that flat bands do not need to be energetically isolated to maximize the critical temperature, showing that many more materials are candidates for superconductivity at elevated temperatures.

Revisiting flat band superconductivity: Dependence on minimal quantum metric and band touchings