We investigate $\mathcal{P}\mathcal{T}$ -symmetric quantum systems ultraweakly coupled to an environment. We find that such open systems evolve under $\mathcal{P}\mathcal{T}$ -symmetric, purely dephasing and unital dynamics. The dynamical map describing the evolution is then determined explicitly using a quantum canonical transformation. Furthermore, we provide an explanation of why $\mathcal{P}\mathcal{T}$ -symmetric dephasing-type interactions lead to a critical slowing down of decoherence. This effect is further exemplified with an experimentally relevant system, a $\mathcal{P}\mathcal{T}$ -symmetric qubit easily realizable, e.g., in optical or microcavity experiments.We investigate $\mathcal{P}\mathcal{T}$-symmetric quantum systems ultraweakly coupled to an environment. We find that such open systems evolve under $\mathcal{P}\mathcal{T}$-symmetric, purely dephasing and unital dynamics. The dynamical map describing the evolution is then determined explicitly using a quantum canonical transformation. Furthermore, we provide an explanation of why $\mathcal{P}\mathcal{T}$-symmetric dephasing-type interactions lead to a critical slowing down of decoherence. This effect is further exemplified with an experimentally relevant system, a $\mathcal{P}\mathcal{T}$-symmetric qubit easily realizable, e.g., in optical or microcavity experiments.

arXiv:1607.05778Physical Review AOct 27, 201652 citations

Quantum Behavior of a PT -Symmetric Two-Mode System with Cross-Kerr Nonlinearity

Jan Peřina, A. Lukš

Quantum behavior of two oscillator modes, with mutually balanced gain and loss and coupled via linear coupling (including energy conserving as well as energy non-conserving terms) and nonlinear cross-Kerr effect, is investigated. Stationary states are found and their stability analysis is given. Exceptional points for PT -symmetric cases are identified. Quantum dynamics treated by the model of linear operator corrections to a classical solution reveals nonclassical properties of individual modes (squeezing) as well as their entanglement.Quantum behavior of two oscillator modes, with mutually balanced gain and loss and coupled via linear coupling (including energy conserving as well as energy non-conserving terms) and nonlinear cross-Kerr effect, is investigated. Stationary states are found and their stability analysis is given. Exceptional points for PT -symmetric cases are identified. Quantum dynamics treated by the model of linear operator corrections to a classical solution reveals nonclassical properties of individual modes (squeezing) as well as their entanglement.

SymmetryAug 7, 201914 citations

Propagation of Quantum Squeezed Light through a Non-Hermitian Bilayer: Effective Medium Theory

Elnaz Pilehvar, Ehsan Amooghorban, Mohammad Kazem Moravvej‐Farshi

In this paper, we investigate the dispersion and medium effects of non-Hermitian bilayer structures consisting of gain and loss layers on the squeezing property of an obliquely incident squeezed light for s- and p-polarized light, in particular at a discrete set of frequencies for which these structures hold PT-symmetric. For this purpose, we calculate the quadrature squeezing of the output state using the QOEMT. The results show although the squeezing property of the output light is retained for the incident frequency farther from the emission frequency of the gain layer, the output light is not squeezed in the PT-symmetric phase.In this paper, we investigate the dispersion and medium effects of non-Hermitian bilayer structures consisting of gain and loss layers on the squeezing property of an obliquely incident squeezed light for s- and p-polarized light, in particular at a discrete set of frequencies for which these structures hold PT-symmetric. For this purpose, we calculate the quadrature squeezing of the output state using the QOEMT. The results show although the squeezing property of the output light is retained for the incident frequency farther from the emission frequency of the gain layer, the output light is not squeezed in the PT-symmetric phase.

Workshop on Recent Advances in Photonics (WRAP)Mar 4, 20221 citation

We investigate

\mathcal{P}\mathcal{T}

-symmetric quantum systems ultraweakly coupled to an environment. We find that such open systems evolve under

\mathcal{P}\mathcal{T}

-symmetric, purely dephasing and unital dynamics. The dynamical map describing the evolution is then determined explicitly using a quantum canonical transformation. Furthermore, we provide an explanation of why

\mathcal{P}\mathcal{T}

-symmetric dephasing-type interactions lead to a critical slowing down of decoherence. This effect is further exemplified with an experimentally relevant system, a

\mathcal{P}\mathcal{T}

-symmetric qubit easily realizable, e.g., in optical or microcavity experiments.