The optical analogues of Bloch oscillations and their associated Wannier-Stark ladders have been recently analyzed. In this Letter we propose an elastic realization these ladders, employing for purpose the torsional vibrations specially designed one-dimensional systems. We measured, first time, ladder wave amplitudes, which are not directly accessible either in quantum-mechanical or cases. amplitudes spatially localized coincide rather well with theoretically predicted amplitudes. rods...

To measure and detect elastic waves in metallic rods a low-frequency electromagnetic-acoustic transducer has been developed. Frequencies range from few hertz up to hundreds of kilohertz. With appropriate configuration the transducer, compressional or torsional can be selectively excited detected. Although used many different situations, it tested applied locally periodic rod, which consists finite number unit cells. The measured wave amplitudes are compared with theoretical ones, obtained...

The flexural vibrations of a locally periodic rod, which consists N unit cells, are discussed both from the experimental and theoretical points view. Timoshenko’s beam theory transfer matrix method used to calculate normal-mode frequencies amplitudes. values then compared with ones, obtained using an electromagnetic acoustic transducer (EMAT). Good agreement between numerical results measurements is obtained. It shown that as grows, band spectrum emerges.

We study, both experimentally and numerically, the Anderson localization phenomenon in torsional waves of a disordered elastic rod, which consists cylinder with randomly spaced notches. find that normal-mode wave amplitudes are exponentially localized as occurs solids. The length is measured using these it shown to decrease function frequency. spectrum also well computed, so its level statistics can be analyzed. Fitting nearest-neighbor spacing distribution repulsion parameter defined varies...

Get PDF Email Share with Facebook Tweet This Post on reddit LinkedIn Add to CiteULike Mendeley BibSonomy Citation Copy Text D. Malacara, I. Rizo, and A. Morales, "Interferometry the Doppler Effect," Appl. Opt. 8, 1746-1747 (1969) Export BibTex Endnote (RIS) HTML Plain alert Save article

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The doorway state phenomenon has been recently analysed in many different systems, both quantum and classical. systems range from nuclei to sedimentary valleys, therefore covering a size of 19 orders magnitude. It also applies with chaotic spectra as well integrable systems. In all these works, the discussed only energy or frequency domains. this letter we present numerical experimental results for quasi–one-dimensional elastic system which presents and, first time, temporal evolution is...

Two elastic systems are considered in this work: A special linear chain of harmonic oscillators and a quasi one-dimensional vibrating rod. Starting both cases with locally periodic system formed by unit cells single element, these converted into binary cells. The acoustic optical bands then appear. For the rod experimental values compared theoretical results; particular, normal-mode amplitudes obtained agreement is excellent.

A simple laser refractometer based on the detection of critical angle for liquids is presented. The calibrated presents up to 0.000 11 uncertainty when refractive index in range between 1.300 00 and 1.340 00. experimental setup easy construct material needed available at most optics laboratories. calibration method can be used other devices. measurements aqueous solutions sodium chloride were carried out test device a linear dependence salt concentration was found.

We study the normal modes of torsional waves in an elastic beam consisting a set N cuboids varying heights.We present experimental, theoretical, and numerical results.We show that some analogies to Wannier-Stark ladders resonances, originally introduced by Wannier 1962, are exhibited this classical system.The original studied consist series equidistant energy levels for electrons crystal presence static external electric field with nearestneighbor level spacing proportional intensity...

The doorway-state phenomenon has been observed in many quantum and classical undulatory systems when two oscillating are coupled, one that a high level density the other very low density. Up to now analysed have common they governed by second-order differential equations. In present work it is shown doorway state mechanism also appears dealing with flexural vibrations of elastic systems, which fourth-order It should be mentioned this emerges from coupled Navier

By analyzing the vibrations of an elastic beam having a locally periodic structure with two defects located symmetrically respect to center beam, we show both theoretically and from experimental point view that localized wave functions, one symmetric other antisymmetric, are produced at position defects. This is example classical tunnel effect.

An alternative formulation of the second law thermodynamics is presented in terms twin systems thermal equilibrium. This allows a direct derivation thermodynamic variables absolute temperature and entropy. The efficiency Carnot cycles also derived. Irreversible processes are defined part two Kelvin-Planck Clausius statements

The phenomenon of the Anderson localization waves in elastic systems is studied.We analyze this two dierent sets systems: disordered linear chains harmonic oscillators and rods which oscillate with torsional waves.The rst set analyzed numerically whereas second one studied both experimentally theoretically.In particular, we discuss properties as a function frequency.In doing that have used inverse participation ratio, related to length.We nd normal modes localize exponentially according...

Abstract Normally, the properties of evanescent optical waves are obtained by developing Fresnel equations that expressed in complex numbers field when incident angle exceeds critical angle. Instead using numbers, here we use real functions and mathematical concept linear independence to obtain all waves.

In a previous work an elastic bar with groove or notch that presents doorway state was studied when the system excited 20 cycles of harmonic signals. The strength function had Lorentzian width Γd = 1/πτd, where τd is decay time prompt response. present paper, doorway-state phenomenon analyzed again for same signals but very large number cycles. strength-function once more obtained, now Γ′ which larger than Γd. A qualitative and numerical explanation this fact given, leading therefore to...

We have designed and tested a traveling, Michelson-type vertical wavemeter for the wavelength measurement of tunable continuous-wave lasers in visible part spectrum. The interferometer has two movable corner cubes, suspending vertically from driving setup resembling Atwood’s machine. To reduce fraction-of-fringe error, vernier-type coincidence circuit was used. Although simple, this relative precision 3.2 parts 109 an overall fringe count about 7×106.