Universal feedback control of two-qubit entanglement

Rafiee, Morteza; Nourmandipour, Alireza; Mancini, Stefano

doi:10.1103/physreva.96.012340

“…Although the classical driving field has a constructive role in preserving the initial entanglement, it does not completely preserve the initial entanglement. Here we intend to examine the possible role of an interaction term among the two qubits on the entanglement dynamics 28 . To this end, we consider the following extra Hamiltonian in relation ( 4 ) in which J is the coupling constant.…”

Section: Similar Qubitsmentioning

confidence: 99%

Entanglement protection of classically driven qubits in a lossy cavity

Nourmandipour

¹

,

Vafafard

²

,

Mortezapour

³

et al. 2021

Sci Rep

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Quantum technologies able to manipulating single quantum systems, are presently developing. Among the dowries of the quantum realm, entanglement is one of the basic resources for the novel quantum revolution. Within this context, one is faced with the problem of protecting the entanglement when a system state is manipulated. In this paper, we investigate the effect of the classical driving field on the generation entanglement between two qubits interacting with a bosonic environment. We discuss the effect of the classical field on the generation of entanglement between two (different) qubits and the conditions under which it has a constructive role in protecting the initial-state entanglement from decay induced by its environment. In particular, in the case of similar qubits, we locate a stationary sub-space of the system Hilbert space, characterized by states non depending on the environment properties as well as on the classical driving-field. Thus, we are able to determine the conditions to achieve maximally entangled stationary states after a transient interaction with the environment. We show that, overall, the classical driving field has a constructive role for the entanglement protection in the strong coupling regime. Also, we illustrate that a factorable initial-state can be driven in an entangled state and, even, in an entangled steady-state after the interaction with the environment.

show abstract

“…Although the classical driving field has a constructive role in preserving the initial entanglement, it does not completely preserve the initial entanglement. Here we intend to examine the possible role of an interaction term among the two qubits on the entanglement dynamics 29 . To this end, we consider the following extra Hamiltonian in relation ( 4)…”

Section: Improvement Of the Preservation Of Entanglementmentioning

confidence: 99%

Entanglement Protection of Classically Driven Qubits in a Lossy Cavity

Nourmandipour¹,

Vafafard²,

Mortezapour³

et al. 2021

Preprint

Self Cite

0

View full text Add to dashboard Cite

Quantum technologies able to manipulating single quantum systems, are presently developing. Among the dowries of the quantum realm, entanglement is one of the basic resources for the novel quantum revolution. Within this context, one is faced with the problem of protecting the entanglement when a system state is manipulated. In this paper, we investigate the effect of the classical driving field on the generation entanglement between two qubits interacting with a bosonic environment. We discuss the effect of the classical field on the generation of entanglement between two (different) qubits and the conditions under which it has a constructive role in protecting the initial-state entanglement from decay induced by its environment. In particular, in the case of similar qubits, we locate a stationary sub-space of the system Hilbert space, characterized by states non depending on the environment properties as well as on the classical driving-field. Thus, we are able to determine the conditions to achieve maximally entangled stationary states after a transient interaction with the environment. We show that, overall, the classical driving field has a constructive role for the entanglement protection in the strong coupling regime. Also, we illustrate that a factorable initial-state can be driven in an entangled state and, even, in an entangled steady-state after the interaction with the environment.

show abstract

“…Actually, quantum feedback has been already proposed for controlling entanglement degradation in interacting systems (see e.g. [10][11][12][13]). Interestingly, these strategies can be implemented in several experiments [14].…”

Section: Introductionmentioning

confidence: 99%