Qubit-flip-induced cavity mode squeezing in the strong dispersive regime of the quantum Rabi model

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.

Scrambling and complexity in phase space

“…Additionally, realizing genuine scrambling requires strong non-Gaussian operations. Candidate experimental platforms for detecting CV scrambling should feature both of these properties, and might include non-linear crystals, cavities [50,94,95], and optical Floquet systems [96].…”

“…For concreteness, we focus on cavity-QED architectures. All Gaussian operations (displacements, beamsplitters, and squeezing operations) can be implemented in these systems [95]. Furthermore, non-Gaussian effects are typically much stronger than in other platforms.…”

Enhancement of squeezing in the Rabi model with parametric nonlinearity

“…This reveals the importance of the CRT's to comprehend the behaviour of full quantum Rabi model for all regimes of the coupling strengths [27][28][29][30][31][32][33][34][35][36][37][38]. In a recent work [39], qubit-flip-induced cavity mode squeezing in the strong coupling regime of the quantum Rabi model has been investigated. Thus it naturally grows an interest to study the enhancement of squeezing in the Rabi model in presence of a parametric nonlinearity in the strong coupling domain.…”

Quantum Mechanical Engine for the Quantum Rabi Model

“…This model has been considered for several applications in quantum information processing [ 33 , 47 , 48 , 49 , 50 , 51 ]. The ratio between the coupling strength and the resonator frequency ( ∼ ) separates the behavior of the system into different regimes [ 52 , 53 ].…”