Abstract
Squeezed states of light are a set of nonclassical states in which the quantum fluctuations of one quadrature component are reduced below the standard quantum limit. With less noise than the best stabilised laser sources, squeezed light is a key resource in the field of quantum technologies and has already improved sensing capabilities in areas ranging from gravitational wave detection to biomedical applications. In this work we propose a novel technique for generating squeezed states of a confined light field strongly coupled to a two-level system, or qubit, in the dispersive regime. Utilising the dispersive energy shift caused by the interaction, control of the qubit state produces a time-dependent change in the frequency of the light field. An appropriately timed sequence of sudden frequency changes reduces the quantum noise fluctuations in one quadrature of the field well below the standard quantum limit. The degree of squeezing and the time of generation are directly controlled by the number of frequency shifts applied. Even in the presence of realistic noise and imperfections, our protocol promises to be capable of generating a useful degree of squeezing with present experimental capabilities.
Highlights
Squeezed states of light are a set of nonclassical states in which the quantum fluctuations of one quadrature component are reduced below the standard quantum limit
Squeezed light was historically generated through nonlinear optical interactions, but over the years the field has expanded and different physical systems are currently pursued in this direction, including superconducting, microwave and optomechanical cavities
We have proposed a new scheme of generating squeezing of a boson field interacting with a qubit under the strong dispersive regime of the quantum Rabi model
Summary
Defining the parameter 2φ =g2/Δ+g2/(2Ω −Δ), the dispersive Hamiltonian may be re-expressed as In this form it is evident that the first term contains a shift in the frequency of the cavity mode that depends on the state of the qubit through σz. The final term of the dispersive Hamiltonian is of interest It takes the form of a one-mode squeezing interaction, the sign of which again depends on the state of the qubit through σz[19]. Violation of the condition effectively signals the breakdown of the dispersive approximation, which is based on second-order non-degenerate perturbation theory in the interaction term, i.e. g is assumed to be small This treatment is valid for both Ω ≫ω and Ω ≪ω but diverges near resonance.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
