Non-Gaussian superradiant transition via three-body ultrastrong coupling

Switchable Superradiant Phase Transition with Kerr Magnons

“…Introduction.-With the experimental advances into the era of ultra-strong coupling in light-matter interactions [1,2] and the theoretical efforts on the fundamental Quantum Rabi model (QRM) , finite-component quantum phase transitions (QPTs) have recently received an increasing attention [5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Practical applications of the finite-component QPTs have been exploited in critical quantum metrology and quantum information science [39][40][41][42][43][44][45].…”

“…By varying the coupling strength, the ground state of the system changes abruptly from the normal phase (NP) to the supperadiant phase (SP) with a boost of photon number. Due to this exotic behavior, the SPT has been widely studied [5][6][7][8][9][10][11][12][13][14][15][16][17][18][50][51][52][53][54][55][56]. Besides the Dicke model, the QRM [30-32, 57, 58], describing the interaction between a single TLS (with level splitting Ω) and a single-mode field (with frequency ω), can also predict the SPT in the low-frequency limit (i.e., ω/Ω → 0) as a replacement of thermodynamic limit [5][6][7][8][9][10][11][12][13][14][15][16][17][18]59].…”

“…Due to this exotic behavior, the SPT has been widely studied [5][6][7][8][9][10][11][12][13][14][15][16][17][18][50][51][52][53][54][55][56]. Besides the Dicke model, the QRM [30-32, 57, 58], describing the interaction between a single TLS (with level splitting Ω) and a single-mode field (with frequency ω), can also predict the SPT in the low-frequency limit (i.e., ω/Ω → 0) as a replacement of thermodynamic limit [5][6][7][8][9][10][11][12][13][14][15][16][17][18]59]. Both the Dicke model and the QRM can be experimentally realized in cavity quantum electrodynamics (CQED) or circuit systems [1,2,[60][61][62][63][64].…”