The Driven Multilevel Atom

Mark P. Silverman

S. Agarwal, Asier Piñeiro Orioli, James K. Thompson +1 more

We investigate the driven-dissipative dynamics of multilevel atomic arrays interacting via dipolar interactions at subwavelength spacings. Unlike two-level atoms in the weakly excited regime, multilevel atoms can become strongly entangled. The entanglement manifests as the growth of spin waves in the ground-state manifold and survives after turning off the drive. We propose the 2.9 μm transition between ^{3}P_{2}↔^{3}D_{3} in ^{88}Sr with 389 nm trapping light as a platform to test our predictions and explore many-body physics with light-matter interactions.

Yulia E. Shchadilova, Mor M. Roses, Emanuele G. Dalla Torre +2 more

We present a fermionic description of nonequilibrium multilevel systems. Our approach uses the Keldysh path-integral formalism and allows us to take into account periodic drives, as well as dissipative channels. The technique is based on the Majorana fermion representation of spin-1/2 models which follows earlier applications in the context of spin and Kondo systems. We apply this formalism to problems of increasing complexity: a dissipative two-level system, a driven-dissipative multilevel atom, and a generalized Dicke model describing many multilevel atoms coupled to a single cavity. We compare our theoretical predictions with recent QED experiments and point out the features of a counterlasing transition. Our technique provides a convenient and powerful framework for analyzing driven-dissipative quantum systems, complementary to other approaches based on the solution of Lindblad master equations.

Harold J. Metcalf, P. van der Straten

A. G. Antipov, Evgenii N. Borisov, N. I. Matveeva +3 more

We study the distortions in the dispersion and absorption spectra that arise when rotating wave approximation (RWA) is applied to multilevel atomic system driven by a polychromatic field. The density matrix equations are solved numerically without applying the RWA and when using it. The obtained polarization spectra are compared with each other in terms of maximum and frequency-averaged deviations.