Cooper quartet correlations in multi-component fermionic systems
田島裕之
東京大学
日時：2022年04月14日（木） 13:30-
場所：オンライン
The Bardeen-Cooper-Schrieffer (BCS) theory for superconductors made a significant impact on modern physics. In particular, the Cooper pair formation plays a central role in the condensation phenomena of many-fermion systems such as electrons, nucleons, quarks, as well as Fermi atomic gases. While the Cooper pairing can be dominant in two-component fermionic systems (i.e., spin-1/2 fermion), a similar object involving more than two fermions may appear in multi-component systems. Recently, the possibility of condensed Cooper quartet (four-body counterpart of Cooper pair) has been discussed theoretically in finite nuclei [1,2]. In this talk, we discuss the possibility of Cooper quartet condensation in the infinite matter at thermodynamic limit [3,4]. The BCS-type variational wave function is extended to the quartet condensation. We apply it to the four-component fermionic systems such as symmetric nuclear matter and electron-hole systems and discuss the possible consequences of Cooper quartet correlations.