In this talk, we study unconventional superconductivity in flat band systems, i.e. a system where the kinetic energy of an electron is almost a constant independent of electron momentum. We find that due to an emergent SU(2) symmetry, the ideal flat-band limit is exactly solvable, and the system shall have infinite many degenerate ground states. In a real system, energy bands are not infinitely flat, and the finite bandwidth lifts this infinite degeneracy, resulting in an unconventional superconductor. We will compare this superconductor with conventional (BCS) superconductors to demonstrate its unconventional features, such as diverging compressibility and pseudo-gap.

Zoom link: https://umich.zoom.us/j/95412705230 Passcode: 055118