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

Sensors

A Pair of Coupled Waveguides as a Classical Analogue for a Solid-State Qubit

Andrey E. Schegolev, N. V. Klenov, Anna V. Bogatskaya, Rustam D. Yusupov, A. M. Popov

Published Oct 28, 2022• 1 citation
Publisher

Abstract

We have determined conditions when a pair of coupled waveguides, a common element for integrated room-temperature photonics, can act as a qubit based on a system with a double-well potential. Moreover, we have used slow-varying amplitude approximation (SVA) for the "classical" wave equation to study the propagation of electromagnetic beams in a couple of dielectric waveguides both analytically and numerically. As a part of an extension of the optical-mechanical analogy, we have considered examples of "quantum operations" on the electromagnetic wave state in a pair of waveguides. Furthermore, we have provided examples of "quantum-mechanical" calculations of nonlinear transfer functions for the implementation of the considered element in optical neural networks.

DOI
10.3390/s22218286

Related papers

‘Quantum effects’ for classical light in modern waveguide circuits

Anna V. Bogatskaya, N. V. Klenov, Maxim V Tereshonok +1 more

Abstract Here we use approaches and concepts from quantum mechanics in order to analyze the propagation of classical electromagnetic waves in the elements of integrated optical circuits. These waveguide circuits are considered as potential wells between complex-shapes barriers formed by opaque media. This allowed us to construct in the framework of the slow-varying amplitude approximation for the wave equation an analogy between coherent oscillations in a quantum system and the redistribution in space of the field strength of a classical wave. We also demonstrated the methods to control the mode composition of a classical light in a spatially inhomogeneous waveguide structure. The proposed description was based on the analogy with Rabi-type oscillations in quantum mechanics.

Laser Physics Letters•Apr 12, 2019•2 citations

Quantization of coupled waveguided modes progression in integrated photonic devices

Jesús Liñares, María C. Nistal, David Barral +2 more

In this work is presented a macroscopic quantum-mechanical analysis of quantum light progression in different kinds of integrated photonic waveguide structures with coupled modes, and therefore with validity, for instance, for integrated optical waveguides (conventional integrated optics), photonic crystal waveguides, nano-optical waveguides (plasmonic modes) and so on. The main goal of the work is to give a consistent and explicit derivation of the quantum Momentum operator, and therefore to calculate the corresponding Heisenberg's Equations. Quantum propagation of nonclassical light states are analyzed in different linear and nonlinear integrated devices.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Apr 25, 2008•0 citations

Design and applications of single-photon devices based on waveguides coupled to quantum emitters

Golam Bappi

Engineering photon-photon interactions is fundamentally challenging because photons in vacuum do not interact with each other. While their interactions can be mediated using optical nonlinearities, these effects are negligible for individual photons. This thesis explores two topics related to optical nonlinearities in waveguides. In the first part, we perform a numerical simulation study of hollow core antiresonant reflecting optical waveguides (ARROWs) fabricated using standard lithographic techniques in the context of their suitability as a platform for on-chip photonic quantum information processing. We investigate the effects of the core size, the number of pairs of antiresonant layers surrounding the hollow core, and the refractive index contrast between cladding materials on propagation losses in the waveguide. Additionally, we explore the feasibility of integrating these waveguides with Bragg gratings and dielectric metasurface mirrors to form on-chip cavities, that when loaded with atomic ensembles could act as nonlinear optical devices controllable with single photons. \n \nThe second part of this thesis studies the application of a 3 level quantum emitter coupled to a directional optical waveguide to deterministically subtract a single photon from a propagating optical pulse. Subtracting a single photon from a light state is one of the most fundamental operations with important applications in quantum information processing. However, current methods to subtract a photon such as using a low reflectivity beam splitter suffer from inherently low success probabilities as well as a strong dependence on the number of photons in the input. We explore implementing this single photon subtraction operation in our proposed system when the optical input is a continuous wave coherent state, coherent pulsed state containing a finite number of photons, or a Fock state.

•Oct 28, 2016•0 citations

Quantum propagation in fibers and waveguides

P. D. Drummond, Mark S. Hillery

Optical fibers are the backbone of the world's communication systems. They also represent the simplest example of a photonic device, where photons in waveguides replace electrons in wires. More sophisticated devices than this can be made, in which all the optical components – including multiple waveguided modes – are integrated on a chip. It is important to understand the quantum noise properties of these systems. While in some respects these systems can be treated as one-dimensional, there are additional features. Dispersion is due not just to material properties, but also to the waveguide geometry. The nonlinearity comes from a combination of material and geometric properties as well. There is, of course, a quantum aspect to these photonic devices, in which quantum noise occurs due to random effects caused by nonlinearity and gain. Optical devices based on waveguides are, of course, not just simple fibers. One can have multiple waveguides with various types of linear coupling. The intrinsic nonlinearity of the dielectric leads to four-wave mixing, which can be an important source of correlated photons, both for fundamental tests of quantum mechanics, and for applications in quantum information. It is often essential to include effects due to anisotropies of various types, as well as material dispersion. In dielectrics, another effect that should be included is the coupling of vibrational modes of the (solid) dielectric to the propagating field, which gives rise to Raman and Brillouin scattering effects. This allows us to obtain a more detailed and correct theory of quantum noise than the simplified case treated in Chapter 3.

Cambridge University Press eBooks•Mar 27, 2014•0 citations

Photon pair generation in quadratic waveguide arrays: A classical optical simulation

Markus Gräfe, Alexander S. Solntsev, Robert Keil +5 more

This work reveals that linear propagation of classical light beams can be used to simulate the nonlinear effect of SPDC leading to photon pair generation and quantum random walks of the generated biphotons. In particular, the authors demonstrate that the quantum correlations of biphotons generated in a quadratically nonlinear 1D waveguide array can be mapped onto a linear beam propagation in specially designed 2D array of coupled optical waveguides. This analogy enables us to simulate, with classical light, the quantum coincidence counts for biphotons including the regime of breaking a 1D Bell like inequality as indicated by positve values of the non-classicality.

Conference on Lasers and Electro-Optics Europe & European Quantum Electronics Conference (CLEO/Europe-EQEC)•May 1, 2013•0 citations

Generation of Coherent and Spatially Squeezed States of an Electromagnetic Beam in a Planar Inhomogeneous Dielectric Waveguide

Anna V. Bogatskaya, Andrey E. Schegolev, N. V. Klenov +1 more

We use slow-varying amplitude approximation (SVA) for the wave equation to study both analytically and numerically propagation of an electromagnetic beam in the waveguide structure with parabolic susceptibility spatial dependence. Such a structure is similar to the harmonic oscillator in quantum mechanics. We analyze this structure as a single mode guide and introduce the notion of number of “photons” in the mode. In particular, we pay special attention to the possibility of effective build-up of the coherent and spatially squeezed vacuum states of the mode that can be of interest for a number of practical applications. The way to provide these types of mode excitation is suggested. Several applications for controlling the mode composition of an electromagnetic wave in the parabolic index-gradient waveguide for various frequency ranges are considered.

Photonics•Jul 30, 2019•3 citations
We have determined conditions when a pair of coupled waveguides, a common element for integrated room-temperature photonics, can act as a qubit based on a system with a double-well potential. Moreover, we have used slow-varying amplitude approximation (SVA) for the "classical" wave equation to study the propagation of electromagnetic beams in a couple of dielectric waveguides both analytically and numerically. As a part of an extension of the optical-mechanical analogy, we have considered examples of "quantum operations" on the electromagnetic wave state in a pair of waveguides. Furthermore, we have provided examples of "quantum-mechanical" calculations of nonlinear transfer functions for the implementation of the considered element in optical neural networks.
Abstract Here we use approaches and concepts from quantum mechanics in order to analyze the propagation of classical electromagnetic waves in the elements of integrated optical circuits. These waveguide circuits are considered as potential wells between complex-shapes barriers formed by opaque media. This allowed us to construct in the framework of the slow-varying amplitude approximation for the wave equation an analogy between coherent oscillations in a quantum system and the redistribution in space of the field strength of a classical wave. We also demonstrated the methods to control the mode composition of a classical light in a spatially inhomogeneous waveguide structure. The proposed description was based on the analogy with Rabi-type oscillations in quantum mechanics.
In this work is presented a macroscopic quantum-mechanical analysis of quantum light progression in different kinds of integrated photonic waveguide structures with coupled modes, and therefore with validity, for instance, for integrated optical waveguides (conventional integrated optics), photonic crystal waveguides, nano-optical waveguides (plasmonic modes) and so on. The main goal of the work is to give a consistent and explicit derivation of the quantum Momentum operator, and therefore to calculate the corresponding Heisenberg's Equations. Quantum propagation of nonclassical light states are analyzed in different linear and nonlinear integrated devices.
Engineering photon-photon interactions is fundamentally challenging because photons in vacuum do not interact with each other. While their interactions can be mediated using optical nonlinearities, these effects are negligible for individual photons. This thesis explores two topics related to optical nonlinearities in waveguides. In the first part, we perform a numerical simulation study of hollow core antiresonant reflecting optical waveguides (ARROWs) fabricated using standard lithographic techniques in the context of their suitability as a platform for on-chip photonic quantum information processing. We investigate the effects of the core size, the number of pairs of antiresonant layers surrounding the hollow core, and the refractive index contrast between cladding materials on propagation losses in the waveguide. Additionally, we explore the feasibility of integrating these waveguides with Bragg gratings and dielectric metasurface mirrors to form on-chip cavities, that when loaded with atomic ensembles could act as nonlinear optical devices controllable with single photons. \n \nThe second part of this thesis studies the application of a 3 level quantum emitter coupled to a directional optical waveguide to deterministically subtract a single photon from a propagating optical pulse. Subtracting a single photon from a light state is one of the most fundamental operations with important applications in quantum information processing. However, current methods to subtract a photon such as using a low reflectivity beam splitter suffer from inherently low success probabilities as well as a strong dependence on the number of photons in the input. We explore implementing this single photon subtraction operation in our proposed system when the optical input is a continuous wave coherent state, coherent pulsed state containing a finite number of photons, or a Fock state.
Optical fibers are the backbone of the world's communication systems. They also represent the simplest example of a photonic device, where photons in waveguides replace electrons in wires. More sophisticated devices than this can be made, in which all the optical components – including multiple waveguided modes – are integrated on a chip. It is important to understand the quantum noise properties of these systems. While in some respects these systems can be treated as one-dimensional, there are additional features. Dispersion is due not just to material properties, but also to the waveguide geometry. The nonlinearity comes from a combination of material and geometric properties as well. There is, of course, a quantum aspect to these photonic devices, in which quantum noise occurs due to random effects caused by nonlinearity and gain. Optical devices based on waveguides are, of course, not just simple fibers. One can have multiple waveguides with various types of linear coupling. The intrinsic nonlinearity of the dielectric leads to four-wave mixing, which can be an important source of correlated photons, both for fundamental tests of quantum mechanics, and for applications in quantum information. It is often essential to include effects due to anisotropies of various types, as well as material dispersion. In dielectrics, another effect that should be included is the coupling of vibrational modes of the (solid) dielectric to the propagating field, which gives rise to Raman and Brillouin scattering effects. This allows us to obtain a more detailed and correct theory of quantum noise than the simplified case treated in Chapter 3.
This work reveals that linear propagation of classical light beams can be used to simulate the nonlinear effect of SPDC leading to photon pair generation and quantum random walks of the generated biphotons. In particular, the authors demonstrate that the quantum correlations of biphotons generated in a quadratically nonlinear 1D waveguide array can be mapped onto a linear beam propagation in specially designed 2D array of coupled optical waveguides. This analogy enables us to simulate, with classical light, the quantum coincidence counts for biphotons including the regime of breaking a 1D Bell like inequality as indicated by positve values of the non-classicality.
We use slow-varying amplitude approximation (SVA) for the wave equation to study both analytically and numerically propagation of an electromagnetic beam in the waveguide structure with parabolic susceptibility spatial dependence. Such a structure is similar to the harmonic oscillator in quantum mechanics. We analyze this structure as a single mode guide and introduce the notion of number of “photons” in the mode. In particular, we pay special attention to the possibility of effective build-up of the coherent and spatially squeezed vacuum states of the mode that can be of interest for a number of practical applications. The way to provide these types of mode excitation is suggested. Several applications for controlling the mode composition of an electromagnetic wave in the parabolic index-gradient waveguide for various frequency ranges are considered.