arXiv:1210.6971 · Communications in Theoretical Physics

Skew Information for a Single Cooper Pair Box Interacting with a Single Cavity Field

NASSER METWALLY, A Mannai, Mahmoud Abdel‐Aty

Published Jun 1, 2013• 8 citations

Abstract

The dynamics of the skew information (SI) is investigated for a single Cooper Pair Box (CPB) interacting with a single cavity field. By suitably choosing the system parameters and precisely controlling the dynamics, novel connection is found between the SI and entanglement generation. It is shown that SI can be increased and reach its maximum value either by increasing the number of photons inside the cavity or considering the far off-resonant case. The number of oscillations of SI is increased by decreasing this ratio between the Josephson junction capacity and the gate capacity. This leads to significant improvement of the travelling time between the maximum and minimum values.

DOI: 10.1088/0253-6102/59/6/20

Related papers

Controlling the transmitted information of a multi-photon interacting with a single-Cooper pair box

Heba Kadry, Abdel‐Haleem Abdel‐Aty, Nordin Zakaria +1 more

We study a model of a multi-photon interaction of a single Cooper pair box with a cavity field. The exchange of the information using this system is studied. We quantify the fidelity of the transmitted information. The effect of the system parameters (detuning parameter, field photons, state density and mean photon number) in the fidelity of the transmitted information is investigated. We found that the fidelity of the transmitted information can be controlled using the system parameters.

AIP conference proceedingsJan 1, 20141 citation

Generation of entangled coherent states of two cavity fields via coupling to a SQUID-based charge qubit

Jie‐Qiao Liao, Le‐Man Kuang

We propose a scheme to generate entangled coherent states (ECSs) of two microwave cavity fields coupling to a SQUID-based Cooper pair box (CPB) charge qubit by extending the single-cavity model of coupling between a single microcavity and a CPB charge qubit proposed by Liu et al (2005 Phys. Rev. A 71 063820). We show that by measuring the states of the CPB charge qubit, ECSs of the two cavity fields can be generated with a controllable interaction between the cavities and the CPB charge qubit.

Journal of Physics B Atomic Molecular and Optical PhysicsMay 1, 200715 citations

Generation of maximally entangled charge-qubit arrays via a cavity mode

Alexandre Guillaume, Jonathan P. Dowling

We describe an assembly of N Cooper-pair boxes (CPB) contained in a single mode cavity. In the dispersive regime, the correlation between the cavity field and each Cooper-pair box results in an effective interaction between CPBs that can be used to dynamically generate maximally entangled states. With only collective manipulations, we show how to create maximally entangled quantum states and how to use these states to reach the Heisenberg limit in the determination of a spectroscopy frequency. This scheme can be applied to other types of superconducting qubits.

arXiv:cond-mat/0508185Aug 8, 20050 citations

DYNAMICAL PROPERTIES OF MULTI-PHOTON INTERACTION BETWEEN A CAVITY FIELD AND A SINGLE-QUBIT

Heba Kadry, Nordin Zakaria, Lee Yen Cheong +1 more

We study the dynamical properties of a cavity field coupling to a Cooper pair box (CPB). We assumed that the CPB is prepared initially in a mixed state with a coherent state for the field. By solving the time-dependent equations using the evolution operator, it shows that mean numbers of Cooper pairs is affected by the detuning. The mean number of Cooper pairs is further enhanced by the multi-photon processes in commonly used cavity field.

International Journal of Quantum InformationJun 1, 20135 citations

Dynamics of encrypted information in superconducting qubits with the presence of imperfect operations

NASSER METWALLY

The original dense coding protocol is achieved via a quantum channel generated between a single Cooper pair and a cavity. The dynamics of the coded and decoded information is investigated for different values of the channel’s parameters. It is shown that these two types of information increase as the detuning parameter increases or the number of photons inside the cavity decreases. The coded and decoded information increases as the ratio of the capacities between the box and the gate decrease. The dynamics of information is investigated in the presence of imperfect operation during the coding process. It is found that, for the phase flip error, the upper bound of the coded and decoded information is much smaller than that depicted for the bit flip errors.

arXiv:1105.0787Journal of the Optical Society of America BFeb 22, 201224 citations

Quantum Entropy of a Single Cooper-Pair Box Interacting with Two Electromagnetic Fields

Bin Shao

A Hamiltonian which represents the interaction between a single Cooper-pair box and two quantized electromagnetic fields is considered in order to find new ways for quantum information. The wave function in Schrdinger picture is obtained. The evolution of the entropy of the box as a function of the scaled time is ploted to measure the entanglement between the box and the fields. It is found that the entanglement is sensitive to the detuning between the Josephson energy and the fields frequency, increasing the detuning can decrease the entanglement.

Journal of Beijing Institute of TechnologyJan 1, 20060 citations