Kicked nonlinear quantum scissors and entanglement generation

Abstract

We consider a nonlinear coupler with two Kerr-like oscillators mutually coupled by continuous linear interaction and excited by a series of ultra-short external pulses. We show that the system behaves as nonlinear quantum scissors. It evolves such a way that it can be treated as qubit-qubit system. We derive analytic formulas for the probabilities of the states involved in the system's evolution and show that they differ from those already discussed in the literature and corresponding to the continuously excited models. Moreover, for model discussed here, maximally entangled Bell states can be generated with high efficiency.

Enhancement of the entanglement generation via randomly perturbed series of external pulses in a nonlinear Bose–Hubbard dimer

“…In the review paper [53] devoted to the formation of truncated quantum states in various nonlinear systems, we have shown that when coupled anharmonic oscillators are excited by ultra-short pulses, the system's evolution can be restricted to a few states only. In [79], when only one of the coupled oscillators was externally driven, we have shown that despite the continual excitations by ultra-short pulses, only four resonant states are populated and in fact, such system behaves as NQS. In consequence, the probability amplitudes corresponding to the populated states |0 |0 , |0 |1 , |1 |0 and |1 |1 show oscillatory behavior with characteristic frequencies describing their evolution [79].…”

“…In [79], when only one of the coupled oscillators was externally driven, we have shown that despite the continual excitations by ultra-short pulses, only four resonant states are populated and in fact, such system behaves as NQS. In consequence, the probability amplitudes corresponding to the populated states |0 |0 , |0 |1 , |1 |0 and |1 |1 show oscillatory behavior with characteristic frequencies describing their evolution [79].…”

“…Our previous considerations, presented in [79] and concerning the possibility of formation of the 2-qubit MES in the similar system, were devoted to the sit-…”

“…First, we shall concentrate on the situation when cross-coupling is omitted (χ 12 = 0). Thus, the equations describing the time evolution of the probability amplitudes are given as in [79] by:…”

Kerr nonlinear coupler and entanglement induced by broadband laser light

“…After "truncation" of the wave function describing the system, the coupler can be treated as two-qubit and treated as a Bell-like state generator that can create maximally entangled states even if the system exhibits its energy dissipating nature [5]. The system behaves similar to nonlinear quantum scissors and maximally entangled Bell states can be generated with high efficiency [6]. * E-mail: khoa_dqspqt@yahoo.com…”