Emission spectrum of a qubit under its deep strong driving in the high-frequency dispersive regime
A. P. Saiko+, S. A. Markevich+, R. Fedaruk*
+Scientific-Practical Material Research Centre, Belarus National Academy of Sciences, 220072 Minsk, Belarus
*Institute of Physics, University of Szczecin, 70-451, Szczecin, Poland
Abstract
We study the emission spectrum of a qubit under deep strong
driving in the high-frequency dispersive regime when the driving
frequency and strength exceed significantly the qubit transition
frequency. Closed-form expressions for the steady-state first-order field
correlation function and the multiphoton emission spectrum are obtained.
The spectrum comprises a series of narrow delta-like lines that stem from
coherent processes and Lorenzian peaks that result from the incoherent
scattering of photons. The oscillating dependence of the widths of the
emission lines on the driving strength is predicted. We show how the
features of this dependence are governed by the qubit dephasing and
relaxation rates.