Generalizing BCS for Exotic Superconductors

A new boson–fermion statistical model with two-hole (h) as well as two-electron (e) Cooper pairs (CP) exhibiting Bose–Einstein condensation (BEC)—which simultaneously reduces to BCS theory in weak coupling for perfect eh symmetry and to BEC when no hole CPs are present—yields reasonable transition temperatures for exotic superconductors, whether quasi-2D cuprate or 3D ones, for moderate departures from perfect eh symmetry.