  We investigate a Rabi-Kondo model describing an optically driven two-channel
quantum dot device featuring a non-Fermi-liquid Kondo effect. Optically induced
Rabi oscillation between the valence and conduction levels of the dot gives
rise to a two-stage Kondo effect: Primary screening of the local spin is
followed by secondary nonequilibrium screening of the local orbital degree of
freedom. Using bosonization arguments and the numerical renormalization group,
we compute the dot emission spectrum and residual entropy. Remarkably, both
exhibit two-stage Kondo screening with non-Fermi-liquid properties at both
stages.
