Precision of single-shot dual-broadband rotational CARS thermometry with single-mode and multi-mode Nd:YAG lasers

2003 ◽  
Vol 34 (12) ◽  
pp. 940-945 ◽  
Author(s):  
M. Afzelius ◽  
P.-E. Bengtsson
Keyword(s):  
Single Mode ◽  
Single Shot ◽  
Nd:Yag Lasers ◽  
Multi Mode

scholarly journals Peta-bit-per-second optical communications system using a standard cladding diameter 15-mode fiber

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Georg Rademacher ◽  
Benjamin J. Puttnam ◽  
Ruben S. Luís ◽  
Tobias A. Eriksson ◽  
Nicolas K. Fontaine ◽  
...  
Keyword(s):  
Wavelength Division Multiplexing ◽  
Single Mode ◽  
Single Mode Fiber ◽  
Capacity Limits ◽  
Wavelength Division ◽  
Core Networks ◽  
Space Division Multiplexing ◽  
Space Division ◽  
Data Rates ◽  
Multi Mode

AbstractData rates in optical fiber networks have increased exponentially over the past decades and core-networks are expected to operate in the peta-bit-per-second regime by 2030. As current single-mode fiber-based transmission systems are reaching their capacity limits, space-division multiplexing has been investigated as a means to increase the per-fiber capacity. Of all space-division multiplexing fibers proposed to date, multi-mode fibers have the highest spatial channel density, as signals traveling in orthogonal fiber modes share the same fiber-core. By combining a high mode-count multi-mode fiber with wideband wavelength-division multiplexing, we report a peta-bit-per-second class transmission demonstration in multi-mode fibers. This was enabled by combining three key technologies: a wideband optical comb-based transmitter to generate highly spectral efficient 64-quadrature-amplitude modulated signals between 1528 nm and 1610 nm wavelength, a broadband mode-multiplexer, based on multi-plane light conversion, and a 15-mode multi-mode fiber with optimized transmission characteristics for wideband operation.

scholarly journals Silicon integrated multi-mode ring resonator

Nanophotonics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 1265-1272
Author(s):  
Mengyuan Ye ◽  
Chunlei Sun ◽  
Yu Yu ◽  
Yunhong Ding ◽  
Xinliang Zhang
Keyword(s):  
Integrated Circuit ◽  
Ring Resonator ◽  
Rapid Development ◽  
Essential Element ◽  
Single Mode ◽  
Modal Dispersion ◽  
Waveguide Width ◽  
Mode Division Multiplexing ◽  
Evanescent Coupling ◽  
Multi Mode

Abstract Ring resonator is an essential element in silicon integrated circuit, it is widely used as filter, wavelength multiplexer and switch in single-mode operation regime. As the rapid development of mode division multiplexing (MDM) technique, ring resonator that can process multi-mode signals simultaneously and uniformly is highly desired. However, the severe modal dispersion makes identical transmission for different modes very hard. In this paper, by breaking through the limitation of conventional multi-mode manipulation design with evanescent coupling or mode interference, we propose and demonstrate a multi-mode ring resonator (MMRR) inspired by the free space geometric optics. Arbitrary number of supporting modes can be achieved by simply widening the waveguide width. For proof-of-concept demonstration, an MMRR supporting four modes is fabricated with uniform transmittance. Furthermore, architecture of cascaded four MMRRs are also demonstrated experimentally.

Depolarization in high power Faraday isolators with single mode and multi-mode laser incidences

2010 ◽  
Vol 22 (6) ◽  
pp. 1229-1233
Author(s):  
葛廷武 Ge Tingwu ◽  
陆丹 Lu Dan ◽  
伍剑 Wu Jian ◽  
徐坤 Xu Kun ◽  
林金桐 Lin Jintong
Keyword(s):  
High Power ◽  
Single Mode ◽  
Mode Laser ◽  
Multi Mode

Modeling of Air Breakdown by Single-Mode and Multi-Mode Lasers

2019 ◽  
Author(s):  
Andrea Alberti ◽  
Alessandro Munafò ◽  
Carlos Pantano ◽  
Jonathan Freund ◽  
Marco Panesi
Keyword(s):  
Single Mode ◽  
Air Breakdown ◽  
Multi Mode

scholarly journals Simple and Accurate Analytical Solutions of the Electrostatically Actuated Curled Beam Problem

2014 ◽  
Author(s):  
Mohammad I. Younis
Keyword(s):  
Analytical Solutions ◽  
Galerkin Approximation ◽  
Single Mode ◽  
Beam Model ◽  
Reduced Order ◽  
Electrostatically Actuated ◽  
Analytical Formulas ◽  
Euler Bernoulli Beam ◽  
Analytical Expressions ◽  
Multi Mode

We present analytical solutions of the electrostatically actuated initially deformed cantilever beam problem. We use a continuous Euler-Bernoulli beam model combined with a single-mode Galerkin approximation. We derive simple analytical expressions for two commonly observed deformed beams configurations: the curled and tilted configurations. The derived analytical formulas are validated by comparing their results to experimental data in the literature and numerical results of a multi-mode reduced order model. The derived expressions do not involve any complicated integrals or complex terms and can be conveniently used by designers for quick, yet accurate, estimations. The formulas are found to yield accurate results for most commonly encountered microbeams of initial tip deflections of few microns. For largely deformed beams, we found that these formulas yield less accurate results due to the limitations of the single-mode approximations they are based on. In such cases, multi-mode reduced order models need to be utilized.

A temperature sensor based on the splicing of a core offset multi-mode fiber with two single mode fiber

2015 ◽  
Vol 11 (6) ◽  
pp. 434-437 ◽  
Author(s):  
Xing-hu Fu ◽  
Qin Liu ◽  
Yan-li Xiu ◽  
Hai-yang Xie ◽  
Chuan-qing Yang ◽  
...  
Keyword(s):  
Temperature Sensor ◽  
Single Mode ◽  
Single Mode Fiber ◽  
Multi Mode

scholarly journals Experimental validation of piezoelectric shunt tuning with residual mode correction: Damping of plate-like structures

2020 ◽  
Vol 31 (9) ◽  
pp. 1220-1239
Author(s):  
Johan Frederik Toftekær ◽  
Jan Høgsberg
Keyword(s):  
Electromechanical Coupling ◽  
Copper Wire ◽  
Short Circuit ◽  
Single Mode ◽  
Magnetic Core ◽  
Open Circuit ◽  
Electromechanical Coupling Coefficient ◽  
Tuning Method ◽  
Multi Mode ◽  
Free Beam

The effective vibration mitigation properties of piezoceramic patches with inductive-resistive shunts are investigated experimentally. A shunt tuning method is proposed, in which a consistent correction for the influence from residual vibration modes is included by an effective modal capacitance, evaluated from measured charge and voltage amplitudes in short- and open-circuit conditions, respectively. The robustness of the proposed method is verified experimentally for both a free beam and a free plate structure with four shunted piezoceramic patch pairs. A stable and fully passive inductor is produced by winding a copper wire around a magnetic core, which requires precise inductance tuning to determine the final number of turns. It is demonstrated that the effective modal capacitance interpolates consistently between the blocked and static capacitances, commonly used for single-mode tuning of piezoelectric inductive-resistive shunts. By imposing pseudo-random vibrations, the piezoelectric current and voltage signals are measured and evaluated by their frequency response functions. Spectrum peak values determine the apparent short-circuit charge to open-circuit voltage ratio for each shunt, which directly determines the shunt components by explicit tuning formulas. Good correlation between numerical and experimental results are obtained for the free beam, while for the free plate experiment effective multi-mode shunt tuning is obtained by a modified effective electromechanical coupling coefficient.

Study on band gap properties of two-dimensional phononic crystals based on generalized viscoelastic modeling

2019 ◽  
Vol 33 (32) ◽  
pp. 1950403
Author(s):  
Fengxiang Guo ◽  
Hui Guo ◽  
Pei Sun ◽  
Tao Yuan ◽  
Yansong Wang
Keyword(s):  
Plane Waves ◽  
Single Mode ◽  
Expansion Method ◽  
Maxwell Model ◽  
Phononic Crystals ◽  
Band Gaps ◽  
Two Dimensional ◽  
Band Structures ◽  
Material Parameters ◽  
Multi Mode

Viscoelastic materials can dissipate energy and hinder propagation for plane waves, which can adjust the band structures of phononic crystals (PCs). In this study, the wave propagation in a two-dimensional PC with a viscoelastic matrix is investigated. The Maxwell model is utilized to analyze the effect of material parameters on the frequency dependence of viscoelasticity. Material parameters include the relaxation time, the initial value and the final value of the shear modulus. Band structures of viscoelastic phononic crystals (VPCs) are solved by combining the plane wave expansion method and iterative algorithm based on Bloch theory. The effects of the viscoelasticity on the band structures are studied using the single-mode and multi-mode Maxwell models. Results reveal that the viscoelasticity of the materials not only extends the band gaps but also shifts the band gaps to lower frequencies. Furthermore, the viscoelasticity simulated by the multi-mode model can precisely adjust anyone of the band gaps of VPCs separately. Results provide insights into the design and applications of VPCs.

Evaluation of turbulent mixing transition in a shock-driven variable-density flow

2017 ◽  
Vol 831 ◽  
pp. 779-825 ◽  
Author(s):  
Mohammad Mohaghar ◽  
John Carter ◽  
Benjamin Musci ◽  
David Reilly ◽  
Jacob McFarland ◽  
...  
Keyword(s):  
Cross Correlation ◽  
Initial Conditions ◽  
Single Mode ◽  
Variable Density ◽  
Transition To Turbulence ◽  
Large Set ◽  
Initial Condition ◽  
Long Wavelength ◽  
Variable Density Flow ◽  
Multi Mode

The effect of initial conditions on transition to turbulence is studied in a variable-density shock-driven flow. Richtmyer–Meshkov instability (RMI) evolution of fluid interfaces with two different imposed initial perturbations is observed before and after interaction with a second shock reflected from the end wall of a shock tube (reshock). The first perturbation is a predominantly single-mode long-wavelength interface which is formed by inclining the entire tube to 80$^{\circ }$ relative to the horizontal, yielding an amplitude-to-wavelength ratio, $\unicode[STIX]{x1D702}/\unicode[STIX]{x1D706}=0.088$, and thus can be considered as half the wavelength of a triangular wave. The second interface is multi-mode, and contains additional shorter-wavelength perturbations due to the imposition of shear and buoyancy on the inclined perturbation of the first case. In both cases, the interface consists of a nitrogen-acetone mixture as the light gas over carbon dioxide as the heavy gas (Atwood number, $A\sim 0.22$) and the shock Mach number is $M\approx 1.55$. The initial condition was characterized through Proper Orthogonal Decomposition and density energy spectra from a large set of initial condition images. The evolving density and velocity fields are measured simultaneously using planar laser-induced fluorescence (PLIF) and particle image velocimetry (PIV) techniques. Density, velocity, and density–velocity cross-statistics are calculated using ensemble averaging to investigate the effects of additional modes on the mixing and turbulence quantities. The density and velocity data show that a distinct memory of the initial conditions is maintained in the flow before interaction with reshock. After reshock, the influence of the long-wavelength inclined perturbation present in both initial conditions is still apparent, but the distinction between the two cases becomes less evident as smaller scales are present even in the single-mode case. Several methods are used to calculate the Reynolds number and turbulence length scales, which indicate a transition to a more turbulent state after reshock. Further evidence of transition to turbulence after reshock is observed in the velocity and density fluctuation spectra, where a scaling close to $k^{-5/3}$ is observed for almost one decade, and in the enstrophy fluctuation spectra, where a scaling close to $k^{1/3}$ is observed for a similar range. Also, based on normalized cross correlation spectra, local isotropy is reached at lower wave numbers in the multi-mode case compared with the single-mode case before reshock. By breakdown of large scales to small scales after reshock, rapid decay can be observed in cross-correlation spectra in both cases.

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