Finite-dimensional states and entanglement generation

We studied a system that has two nonlinear oscillators with different frequencies. These oscillators are coupled via a nonlinear interaction. With the aim of excite the system, we used two external coherent ﬁelds. It follows from numerical simulation that evolution of the system which is likely to be a combination of Fock states. THerefore, the deliberated system behaves as so-called nonlinear quantum scissor. However, evolution of the system generates Bell-like states in some times with exact high probability. The system creates a truncation of optical states, which leads to obtain two-qubit states due to the nonlinear properties of oscillators and their interaction.We studied a system that has two nonlinear oscillators with different frequencies. These oscillators are coupled via a nonlinear interaction. With the aim of excite the system, we used two external coherent ﬁelds. It follows from numerical simulation that evolution of the system which is likely to be a combination of Fock states. THerefore, the deliberated system behaves as so-called nonlinear quantum scissor. However, evolution of the system generates Bell-like states in some times with exact high probability. The system creates a truncation of optical states, which leads to obtain two-qubit states due to the nonlinear properties of oscillators and their interaction.

SCIENTIFIC JOURNAL OF TAN TRAO UNIVERSITYApr 7, 20210 citations

Entangled State Creation by a Nonlinear Coupler Pumped in Two Modes

Vinh Le Duc, Van Cao Long

In this paper we consider a system with two nonlinear oscillators which are coupled via a nonlinear interaction.In order to excite the system, we use two external coherent fields.Two oscillators have different frequencies.It follows from numerical simulation that evolution of the system is similar to that of a combination of n-photon states.Therefore, the considered system behaves as so-called nonlinear quantum scissor.Nevertheless, evolution of the system generates Bell-like states in several times with very high probability.Because of the nonlinear properties of oscillators and their interaction, the system creates a truncation of optical states, which leads to obtain two-qubit states.It will also be shown that these states appear several times in the qutrit-qutrit system.In this paper we consider a system with two nonlinear oscillators which are coupled via a nonlinear interaction.In order to excite the system, we use two external coherent fields.Two oscillators have different frequencies.It follows from numerical simulation that evolution of the system is similar to that of a combination of n-photon states.Therefore, the considered system behaves as so-called nonlinear quantum scissor.Nevertheless, evolution of the system generates Bell-like states in several times with very high probability.Because of the nonlinear properties of oscillators and their interaction, the system creates a truncation of optical states, which leads to obtain two-qubit states.It will also be shown that these states appear several times in the qutrit-qutrit system.

Computational Methods in Science and TechnologyDec 31, 20165 citations

Generation of Maximally Entangled States by a Kerr-like Nonlinear Coupler Interacting with External Fields

Doan Quoc Khoa, Luong Thi Tu Oanh, Chu Van Lanh +2 more

We study a model with two nonlinear oscillators (Kerr-like nonlinear coupler) pumped by two external coherent fields as a nonlinear quantum scissor (NQS). Using the numerical simulation method introduced before for quantum state engineering in NQS of such type, we obtain the wave function describing the evolution of the system as a combination of n-photon states. Considered NQS generates a truncation of optical states that leads to achieve two-qubit states due to the nonlinear properties of oscillators and their interaction. In particular, evolution of the system generates maximally entangled states as so-called Bell-like states. We will show that a proper choice of initial conditions for such evolution implies the increase of efficiency of entanglement creation process. We consider our model for both damping and without damping cases.We study a model with two nonlinear oscillators (Kerr-like nonlinear coupler) pumped by two external coherent fields as a nonlinear quantum scissor (NQS). Using the numerical simulation method introduced before for quantum state engineering in NQS of such type, we obtain the wave function describing the evolution of the system as a combination of n-photon states. Considered NQS generates a truncation of optical states that leads to achieve two-qubit states due to the nonlinear properties of oscillators and their interaction. In particular, evolution of the system generates maximally entangled states as so-called Bell-like states. We will show that a proper choice of initial conditions for such evolution implies the increase of efficiency of entanglement creation process. We consider our model for both damping and without damping cases.

Communications in PhysicsAug 13, 20190 citations

Kerr nonlinear coupler and entanglement

Wies aw Leo ski, Adam Miranowicz

We discuss a model comprising two coupled nonlinear oscillators (Kerr-like nonlinear coupler) with one of them pumped by an external coherent excitation. Applying the method of nonlinear quantum scissors we show that the quantum evolution of the coupler can be closed within a finite set of n -photon Fock states. Moreover, we show that the system is able to generate Bell-like states and, as a consequence, the coupler discussed behaves as a two-qubit system. We also analyse the effects of dissipation on entanglement of formation parametrized by concurrence.We discuss a model comprising two coupled nonlinear oscillators (Kerr-like nonlinear coupler) with one of them pumped by an external coherent excitation. Applying the method of nonlinear quantum scissors we show that the quantum evolution of the coupler can be closed within a finite set of n -photon Fock states. Moreover, we show that the system is able to generate Bell-like states and, as a consequence, the coupler discussed behaves as a two-qubit system. We also analyse the effects of dissipation on entanglement of formation parametrized by concurrence.

arXiv:quant-ph/0408024Journal of Optics B Quantum and Semiclassical OpticsMar 1, 2004105 citations

Kicked nonlinear quantum scissors and entanglement generation

A. Kowalewska-Kudłaszyk, W. Leoński, Thi Dung Nguyen +1 more

We consider a nonlinear coupler with two Kerr-like oscillators mutually coupled by continuous linear interaction and excited by a series of ultrashort external pulses. We show that the system behaves like nonlinear quantum scissors . It evolves in such a way that it can be treated as a 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 the model discussed here, maximally entangled Bell states can be generated with high efficiency.We consider a nonlinear coupler with two Kerr-like oscillators mutually coupled by continuous linear interaction and excited by a series of ultrashort external pulses. We show that the system behaves like nonlinear quantum scissors . It evolves in such a way that it can be treated as a 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 the model discussed here, maximally entangled Bell states can be generated with high efficiency.

arXiv:1404.1735Physica ScriptaApr 1, 201413 citations

Finite-dimensional states and entanglement generation for a nonlinear coupler

A. Kowalewska-Kudłaszyk, W. Leoński

We discuss a system comprising two nonlinear (Kerr-like) oscillators coupled mutually by a nonlinear interaction. The system is excited by an external coherent field that is resonant to the frequency of one of the oscillators. We show that the coupler evolution can be closed within a finite set of $n$ -photon states, analogously as in the nonlinear quantum scissors model. Moreover, for this type of evolution our system can be treated as a Bell-like state generator. Thanks to the nonlinear nature of both oscillators and their internal coupling, these states can be generated even if the system exhibits its energy dissipating nature, contrary to systems with linear couplings.We discuss a system comprising two nonlinear (Kerr-like) oscillators coupled mutually by a nonlinear interaction. The system is excited by an external coherent field that is resonant to the frequency of one of the oscillators. We show that the coupler evolution can be closed within a finite set of $n$-photon states, analogously as in the nonlinear quantum scissors model. Moreover, for this type of evolution our system can be treated as a Bell-like state generator. Thanks to the nonlinear nature of both oscillators and their internal coupling, these states can be generated even if the system exhibits its energy dissipating nature, contrary to systems with linear couplings.

arXiv:quant-ph/0603090Physical Review AApr 24, 200640 citations

n

-photon states, analogously as in the nonlinear quantum scissors model. Moreover, for this type of evolution our system can be treated as a Bell-like state generator. Thanks to the nonlinear nature of both oscillators and their internal coupling, these states can be generated even if the system exhibits its energy dissipating nature, contrary to systems with linear couplings.