Quantum Photonic Simulation of Spin-Magnetic Field Coupling and Atom-Optical Field Interaction

In this work, we present the physical simulation of the dynamical and topological properties of atom-field quantum interacting systems by means of integrated quantum photonic devices. In particular, we simulate mechanical systems used, for example, for quantum processing and requiring a very complex technology such as a spin-1/2 particle interacting with an external classical time-dependent magnetic field and a two-level atom under the action of an external classical time-dependent electric (optical) field (light-matter interaction). The photonic device consists of integrated optical waveguides supporting two collinear or codirectional modes, which are coupled by integrated optical gratings. We show that the single-photon quantum description of the dynamics of this photonic device is a quantum physical simulation of both aforementioned interacting systems. The two-mode photonic device with a single-photon quantum state represents the quantum system, and the optical grating corresponds to an external field. Likewise, we also present the generation of Aharonov–Anandan geometric phases within this photonic device, which also appear in the simulated systems. On the other hand, this photonic simulator can be regarded as a basic brick for constructing more complex photonic simulators. We present a few examples where optical gratings interacting with several collinear and/or codirectional modes are used in order to illustrate the new possibilities for quantum simulation.

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MODELING OF FIBER-OPTIC COMMUNICATION CHANNEL FOR QUANTUM CRYPTOGRAPHIC SYSTEMS

Issues of radio electronics ◽

10.21778/2218-5453-2019-4-90-95 ◽

2019 ◽

pp. 90-95

Author(s):

V. A. Minaev ◽

I. D. Korolev ◽

O. A. Kulish ◽

A. V. Mazin

Keyword(s):

Information Transmission ◽

Information Transfer ◽

Fiber Optic ◽

Single Photon ◽

Optical Devices ◽

Energy Losses ◽

Integrated Optical ◽

Integrated Optical Devices ◽

Fiber Optic Communication ◽

Optic Communication

The existing methods of information delivery to the strategic and tactical management of many government agencies are expensive, not always reliable and efficient. Therefore, quantum cryptographic systems (QCS) have been actively developed in recent years. However, there are problems with the use of the QCS associated with the reliability of information transfer. First, the existing fiber-optic communication channels (FOCC) are not designed to transmit single-photon signals, which leads to the complexity of their cryptographic protection. The second is insufficiently methodically developed calculation of energy losses and errors in the evaluation of the characteristics of information transfer in FOCC QCS. In article the analysis of the energy loss factors in the classical fiber-optic channel is carried out and the additive loss formula is discussed in detail. Then we consider the fiber-optic channel of quantum information transmission with the use of integrated optical devices. The additive formula of optical losses in such a channel is discussed. The features of losses in integrated optical devices are shown. The features of quantum cryptographic system of information transmission are considered. As a result, the model of FOCC QCS taking into account energy losses is presented, which allows competently in theoretical terms and visualize the passage of information through modern quantum cryptographically secure telecommunications while providing control in government structures.

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Holographic selective mode coupling to integrated optical waveguides

Electronics Letters ◽

10.1049/el:19760184 ◽

1976 ◽

Vol 12 (10) ◽

pp. 239 ◽

Cited By ~ 3

Author(s):

O.D.D. Soares ◽

E.A. Ash

Keyword(s):

Optical Waveguides ◽

Mode Coupling ◽

Integrated Optical ◽

Integrated Optical Waveguides

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Moving Pearl Vortices in Thin-Film Superconductors

Condensed Matter ◽

10.3390/condmat6010004 ◽

2021 ◽

Vol 6 (1) ◽

pp. 4

Author(s):

Vladimir Kogan ◽

Norio Nakagawa

Keyword(s):

Magnetic Field ◽

Thin Film ◽

Time Dependent ◽

Superconducting Thin Film ◽

Self Energy ◽

London Equation ◽

The Magnetic Field

The magnetic field hz of a moving Pearl vortex in a superconducting thin-film in (x,y) plane is studied with the help of the time-dependent London equation. It is found that for a vortex at the origin moving in +x direction, hz(x,y) is suppressed in front of the vortex, x>0, and enhanced behind (x<0). The distribution asymmetry is proportional to the velocity and to the conductivity of normal quasiparticles. The vortex self-energy and the interaction of two moving vortices are evaluated.

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Hamiltonian Approach to Magnetic Fields with Toroidal Surfaces

Zeitschrift für Naturforschung A ◽

10.1515/zna-1985-1001 ◽

1985 ◽

Vol 40 (10) ◽

pp. 959-967

Author(s):

A. Salat

Keyword(s):

Magnetic Field ◽

Hamiltonian System ◽

Magnetic Fields ◽

Constant Pressure ◽

Time Dependent ◽

Hamiltonian Approach ◽

One Dimensional ◽

Mhd Equilibrium ◽

Magnetic Surfaces ◽

Rotational Transform

The equivalence of magnetic field line equations to a one-dimensional time-dependent Hamiltonian system is used to construct magnetic fields with arbitrary toroidal magnetic surfaces I = const. For this purpose Hamiltonians H which together with their invariants satisfy periodicity constraints have to be known. The choice of H fixes the rotational transform η(I). Arbitrary axisymmetric fields, and nonaxisymmetric fields with constant η(I) are considered in detail.Configurations with coinciding magnetic and current density surfaces are obtained. The approach used is not well suited, however, to satisfying the additional MHD equilibrium condition of constant pressure on magnetic surfaces.

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Measurements of the time-dependent cosmic-ray Sun shadow with seven years of IceCube data: Comparison with the Solar cycle and magnetic field models

Physical Review D ◽

10.1103/physrevd.103.042005 ◽

2021 ◽

Vol 103 (4) ◽

Author(s):

M. G. Aartsen ◽

R. Abbasi ◽

M. Ackermann ◽

J. Adams ◽

J. A. Aguilar ◽

...

Keyword(s):

Magnetic Field ◽

Solar Cycle ◽

Cosmic Ray ◽

Time Dependent ◽

Data Comparison

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Structure evolution of suspensions under time-dependent electric or magnetic field

Multiscale and Multidisciplinary Modeling Experiments and Design ◽

10.1007/s41939-021-00100-x ◽

2021 ◽

Author(s):

Konstantinos Manikas ◽

Markus Hütter ◽

Patrick D. Anderson

Keyword(s):

Magnetic Field ◽

Field Strength ◽

Brownian Dynamics ◽

Thermal Fluctuations ◽

Time Dependent ◽

Structure Evolution ◽

Strength Increase ◽

Large Rotation ◽

Dynamics Simulations ◽

Brownian Dynamics Simulations

AbstractThe effect of time-dependent external fields on the structures formed by particles with induced dipoles dispersed in a viscous fluid is investigated by means of Brownian Dynamics simulations. The physical effects accounted for are thermal fluctuations, dipole-dipole and excluded volume interactions. The emerging structures are characterised in terms of particle clusters (orientation, size, anisotropy and percolation) and network structure. The strength of the external field is increased in one direction and then kept constant for a certain amount of time, with the structure formation being influenced by the slope of the field-strength increase. This effect can be partially rationalized by inhomogeneous time re-scaling with respect to the field strength, however, the presence of thermal fluctuations makes the scaling at low field strength inappropriate. After the re-scaling, one can observe that the lower the slope of the field increase, the more network-like and the thicker the structure is. In the second part of the study the field is also rotated instantaneously by a certain angle, and the effect of this transition on the structure is studied. For small rotation angles ($$\theta \le 20^{{\circ }}$$ θ ≤ 20 ∘ ) the clusters rotate but stay largely intact, while for large rotation angles ($$\theta \ge 80^{{\circ }}$$ θ ≥ 80 ∘ ) the structure disintegrates and then reforms, due to the nature of the interactions (parallel dipoles with perpendicular inter-particle vector repel each other). For intermediate angles ($$20<\theta <80^{{\circ }}$$ 20 < θ < 80 ∘ ), it seems that, during rotation, the structure is altered towards a more network-like state, as a result of cluster fusion (larger clusters). The details provided in this paper concern an electric field, however, all results can be projected into the case of a magnetic field and paramagnetic particles.

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OBSERVATION OF THE TRANSVERSE STERN–GERLACH EFFECT IN NEUTRAL POTASSIUM

Canadian Journal of Physics ◽

10.1139/p67-112 ◽

1967 ◽

Vol 45 (4) ◽

pp. 1481-1495 ◽

Cited By ~ 25

Author(s):

Myer Bloom ◽

Eric Enga ◽

Hin Lew

Keyword(s):

Magnetic Field ◽

Angular Velocity ◽

Reference Frame ◽

Inhomogeneous Magnetic Field ◽

Time Dependent ◽

Effective Magnetic Field ◽

Classical Analysis ◽

At Resonance ◽

Rotating Reference Frame

A successful transverse Stern–Gerlach experiment has been performed, using a beam of neutral potassium atoms and an inhomogeneous time-dependent magnetic field of the form[Formula: see text]A classical analysis of the Stern–Gerlach experiment is given for a rotating inhomogeneous magnetic field. In general, when space quantization is achieved, the spins are quantized along the effective magnetic field in the reference frame rotating with angular velocity ω about the z axis. For ω = 0, the direction of quantization is the z axis (conventional Stern–Gerlach experiment), while at resonance (ω = −γH0) the direction of quantization is the x axis in the rotating reference frame (transverse Stern–Gerlach experiment). The experiment, which was performed at 7.2 Mc, is described in detail.

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