No-go theorem for the superradiant phase transition without dipole approximation
Krzysztof Gawędzki, Kazimierz Rza̧żewski · Physical Review A · 1981
A diamagnetic inequality is used to extend beyond the dipole approximation an earlier result concerning the nonexistence of the superradiant phase transition.Received 21 July 1980DOI:https://doi.org/10.1103/PhysRevA.23.2134©1981 American Physical Society