Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Journal of the Optical Society of America B

Frequency variations in impulse excitations as a way of entanglement increase in the two-mode Bose–Hubbard model

Joanna K. Kalaga, A. Kowalewska-Kudłaszyk

Published Jul 18, 2019• 2 citations
Publisher

Abstract

A system of two coupled quantum oscillators in the Bose–Hubbard model is discussed as a source of maximally entangled states obtained by ultrashort coherent pulses. Both oscillators are externally driven, and by appropriate relations between the frequencies, we can manipulate the degree of entanglement in bosonic modes. Created entanglement between two subsystems can be controlled and depends strictly on the number of pulses applied to one of the coupler’s parts during a unitary evolution of the other. It is shown that the creation of maximally entangled states is possible, especially for cases when applying other types of excitations (continuous driving or simultaneous excitations) leads to a very weak entanglement of the coupled bosonic system.

DOI
10.1364/josab.36.002140

Related papers

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

Joanna K. Kalaga, A. Kowalewska-Kudłaszyk, M.W. Jarosik +2 more

We discuss a model of a short Bose–Hubbard dimer involving two anharmonic quantum oscillators mutually coupled with the use of the linear interaction and additionally driven by a series of ultra-short external pulses. We show that under some conditions the system behaves as a two-qubit one, and contrary to its continuously driven counterpart can be a source of maximally entangled states (MES). We discuss the cases when the system is excited only in one mode and in both ones, and additionally when the cross-Kerr-type interaction is present or omitted. We show that the generation of maximally (or almost maximally) entangled states depends on the time of free evolution of oscillators and hence, the proper steering of the changes of the time between subsequent pulses can increase the effectiveness of MES generation. Moreover, we show the influence of the timing between two series of pulses (corresponding to the two modes) on such a process. What is relevant, thanks to the presence of additional randomness in the timings, the states with stronger entanglement can be achieved than for the situation when the time between consecutive pulses remains ideally fixed.

Nonlinear Dynamics•Jun 27, 2019•9 citations

Pulsed Nonlinear Coupler as an Effective Tool for the Bell-Like States Generation

Joanna K. Kalaga, M.W. Jarosik, Radosław Szczȩśniak +2 more

We discuss a model consisting of two nonlinear oscillators, where a train of periodic ultrashort laser pulses excites one of them.We show that the system can behave as a two-qubit system and produce maximally entangled Bell states.Such generation is more effective than that for the system with continuous excitation.

Acta Physica Polonica A•Feb 1, 2019•4 citations

Entanglement generation in a system of continuously excited anharmonic quantum oscillators

Joanna K. Kalaga, W. Leoński, Małgorzata Kostrzewa

We discuss a system of two coupled anharmonic Kerr-type quantum oscillators. The oscillators are continuously driven, and the strength of excitation changes periodically. We show that such a system can be a source of strongly entangled states, and the degree of entanglement between two subsystems depends on the period of changes in excitation’s strength.

Polish-Slovak-Czech Optical Conference on Wave and Quantum Aspects of Contemporary Optics•Dec 13, 2022•1 citation

Dissipation-boosted entanglement in coupled harmonic oscillators

Chaitanya S. Joshi, Michael J. W. Hall, M. Jonson +2 more

We theoretically investigate a system of two coupled bosonic modes subject to both dissipation and external driving. We show that in the steady state the degree of entanglement between the coupled bosonic modes can be enhanced by dissipation. The non-monotonic dependence of entanglement on the decay rates is observed when the bosonic modes are asymmetrically coupled to their local baths. This counterintuitive result opens a new way to better understand the interplay between noise and coherence in continuous variable systems driven away from equilibrium.

arXiv:1111.1709•Nov 7, 2011•0 citations

Entanglement created by spontaneously generated coherence

Zhao-Hong Tang, Gao‐xiang Li, Z. Ficek

We propose a scheme that is able to generate on demand a steady-state entanglement between two nondegenerate cavity modes. The scheme relies on the interaction of the cavity modes with driven two- or three-level atoms, which act as a coupler to build entanglement between the modes. We show that, in the limit of a strong driving, it is crucial for the generation of entanglement between the modes to imbalance populations of the dressed states of the driven atomic transition. In the case of a three-level $V$-type atom, we find that a stationary entanglement can be created on demand by tuning the Rabi frequency of the driving field to the difference between the atomic transition frequencies. The resulting degeneracy of the energy levels, together with the spontaneously generated coherence, generate a steady-state entanglement between the cavity modes. It is shown that the condition for the maximal entanglement coincides with the collapse of the atomic system into a pure trapping state. We also show that the creation of entanglement depends strongly on the mutual polarization of the transition atomic dipole moments.

arXiv:1010.1067•Physical Review A•Dec 29, 2010•26 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.

Computational Methods in Science and Technology•Dec 31, 2016•5 citations
A system of two coupled quantum oscillators in the Bose–Hubbard model is discussed as a source of maximally entangled states obtained by ultrashort coherent pulses. Both oscillators are externally driven, and by appropriate relations between the frequencies, we can manipulate the degree of entanglement in bosonic modes. Created entanglement between two subsystems can be controlled and depends strictly on the number of pulses applied to one of the coupler’s parts during a unitary evolution of the other. It is shown that the creation of maximally entangled states is possible, especially for cases when applying other types of excitations (continuous driving or simultaneous excitations) leads to a very weak entanglement of the coupled bosonic system.
We discuss a model of a short Bose–Hubbard dimer involving two anharmonic quantum oscillators mutually coupled with the use of the linear interaction and additionally driven by a series of ultra-short external pulses. We show that under some conditions the system behaves as a two-qubit one, and contrary to its continuously driven counterpart can be a source of maximally entangled states (MES). We discuss the cases when the system is excited only in one mode and in both ones, and additionally when the cross-Kerr-type interaction is present or omitted. We show that the generation of maximally (or almost maximally) entangled states depends on the time of free evolution of oscillators and hence, the proper steering of the changes of the time between subsequent pulses can increase the effectiveness of MES generation. Moreover, we show the influence of the timing between two series of pulses (corresponding to the two modes) on such a process. What is relevant, thanks to the presence of additional randomness in the timings, the states with stronger entanglement can be achieved than for the situation when the time between consecutive pulses remains ideally fixed.
We theoretically investigate a system of two coupled bosonic modes subject to both dissipation and external driving. We show that in the steady state the degree of entanglement between the coupled bosonic modes can be enhanced by dissipation. The non-monotonic dependence of entanglement on the decay rates is observed when the bosonic modes are asymmetrically coupled to their local baths. This counterintuitive result opens a new way to better understand the interplay between noise and coherence in continuous variable systems driven away from equilibrium.
We propose a scheme that is able to generate on demand a steady-state entanglement between two nondegenerate cavity modes. The scheme relies on the interaction of the cavity modes with driven two- or three-level atoms, which act as a coupler to build entanglement between the modes. We show that, in the limit of a strong driving, it is crucial for the generation of entanglement between the modes to imbalance populations of the dressed states of the driven atomic transition. In the case of a three-level VVV-type atom, we find that a stationary entanglement can be created on demand by tuning the Rabi frequency of the driving field to the difference between the atomic transition frequencies. The resulting degeneracy of the energy levels, together with the spontaneously generated coherence, generate a steady-state entanglement between the cavity modes. It is shown that the condition for the maximal entanglement coincides with the collapse of the atomic system into a pure trapping state. We also show that the creation of entanglement depends strongly on the mutual polarization of the transition atomic dipole moments.
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.