Engineering optomechanically induced transparency by coupling a qubit to a spinning resonator

Abstract

We theoretically study the spectral properties of a pump–probe driven hybrid spinning optomechanical ring resonator optically coupled with a two-level quantum emitter (QE or qubit). Recently, we have shown [Opt. Express 27, 25515 (2019)OPEXFF1094-408710.1364/OE.27.025515] that in the absence of the emitter, the coupled cavity version of this setup is not only capable of non-reciprocal light propagation but can also exhibit slow and fast light propagation. In this work, we investigate in what ways the presence of a single QE coupled with the optical whispering gallery modes of a spinning optomechanical resonator can alter the probe light non-reciprocity. Under the weak-excitation assumption and mean-field approximation, we find that the interplay between the rotational/spinning Sagnac effect and qubit coupling can lead to enhancement of both the optomechanically induced transparency peak value and the width of the transparency window due to the opening of a qubit-assisted backreflection channel. However, compared to the no-qubit case, we notice that such enhancement comes at the cost of degrading the group delay in probe light transmission by a factor of 1/2 for clockwise rotary directions. The target applications of these results can be in the areas of quantum circuitry and in non-reciprocal quantum communication protocols where QEs are a key component.