We show the superradiant phase transition (SPT) can control the existence of flat band in an extended Dicke-Hubbard lattice 
G. -L. Zhu, X. -Y. Lü and H. Ramezani, "Characterizing the Quantum Phase Transition using a Flat Band in Circuit QED Lattices," 2020 Conference on Lasers and Electro-Optics (CLEO), San Jose, CA, USA, 2020, pp. 1-2.
2020 Conference on Lasers and Electro-Optics (CLEO)