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Acousto-optical interaction and its advanced applications

ADAN OMAR ARELLANES BERNABE (2013)

In this this work, the acousto-optical interaction is studied. Since its

inception, in 1922, it has been widely studied and applied. Here, the

development of three advanced application of this branch of physics is

considered.

First, is analyzed the potential use of an acousto-optical cell for be included as

a dynamic diffraction grating, in order to improve in many ways the actual

static gratings used, in the Guillermo Haro astrophysical observatory. For

this, it was necessary to estimate the performance of several acousto-optical

materials available today.

Second, a specific mechanism of the acousto-optical nonlinearity is studied to

regulate the performance of the collinear acousto-optical filter. The theory of

this phenomenon is analyzed and confirmed experimentally using and

advanced filter based on calcium molybdate (CaMoO 4 ) single-crystal. The

transmission function of electronically tunable filter exhibits a dependence on

the applied acoustic power density, and as a result, it is possible to squeeze

the transmission function at the cost of decreasing the device efficiency

partially.

And at final, the triple product processor is studied for its potential

application in spectroscopy designed for 3-inch optics and analyzing all the

materials needed for its realization. The need to use 3-inch optics is mainly

oriented to exploit an acousto-optical cells with large aperture windows to get

a large time-bandwidth product.

Master thesis

Acousto-optical devices Acousto-optical effects Acousto-optical filters Acousto-optical signal-processing CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Some aspects of acousto-optical spectrum analysis

KARLA JANETH SANCHEZ PEREZ (2011)

Acousto-optics is the branch of physics devoted to the study of the effects of

the interaction between acoustic and optical waves. For signal analysis systems,

that allow the interaction of sound and light waves, acousto-optical devices are

needed. The advent of lasers made possible, among other things, the practical

use of acousto-optical effect to modulate light for signal transmission and manipulation. It is necessary to characterize the materials, in which the acousto-optical

interaction will be hold, for the proper functioning of these systems.

To determine the usefulness of acousto-optical devices it is necessary to understand the properties of acousto-optical materials, which are desirable to make

acousto-optical devices. This thesis presents the study of two acousto-optical cells

for optical signal and radio signal analysis, namely calcium molybdate and KRS-5

single crystals, respectively.

La acusto-óptica es la rama de la Física que estudia los efectos de la interacción entre ondas acústicas y ópticas. Existen sistemas destinados al análisis de

señales, tales sistemas necesitan dispositivos que permitan la interacción de ondas

de sonido y de luz. La llegada del láser a principios de la década de los años 60

hizo posible, entre otras cosas, el uso del efecto acusto-óptico para modular la luz

en casos de transmisión de señales. Sin embargo, para el correcto funcionamiento

de dichos sistemas es necesario caracterizar los materiales en los cuales se llevará

a cabo la interacción acusto-óptica.

Es necesario analizar los materiales, con los que se desea fabricar dispositivos

acusto ópticos, para determinar si serán útiles en el análisis de señales. En este

trabajo se presenta el estudio realizado sobre dos celdas acusto-ópticas destinadas

al análisis de señales ópticas y señales de radio, dichas celdas acusto-ópticas están

fabricadas de molibdato de calcio y KRS-5, respectivamente

Master thesis

Acousto-optical effects Spectroscopy Optical losses CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Nonlinear acousto-optics: improvements in optical spectrum analysis

ADAN OMAR ARELLANES BERNABE (2016)

In this work, the non-linear acousto-optical interaction is studied for the collinear

and the non-collinear cases. First, a non-linear regime of the collinear acoustooptical

interaction is considered with acoustic waves of finite amplitude

considering the acoustic loses in a crystalline acousto-optical cell. The results of

this analysis were confirmed first in a calcium molybdate (CaMoO4) acoustooptical

cell. After this, the results were extrapolated to predict the performances of

a lithium niobate (LiNbO3) acousto-optical cell oriented to the application in

astrophysical spectroscopy near the ultraviolet range. This material, specifically,

was in need of further analysis due to known phenomena within it that could

affect the capabilities of such cell.

Then, the non-collinear acousto-optical interaction is studied for the multiphonon

light scattering in the Bragg regime. This regime allows only two possible cases

of multiphonon light scattering, namely, the two- and three-phonon acoustooptical

interaction. Together with this, a specific degree of freedom for this

acousto-optical interaction is introduced to regulate the acoustic frequency

necessary for the interaction to occur. The multiphonon light scattering was

theoretically analyzed and experimented in two different crystals; calomel

(Hg2Cl2) for the two-phonon interaction and tellurium dioxide (TeO2) for the

three-phonon case.

En este trabajo se estudia la interacción acusto-óptica no-lineal para los regímenes

colineal y no-colineal. Primero, un régimen no-lineal de la interacción acustoóptica

colineal está bajo consideración con ondas acústicas de amplitud finita

tomando en cuenta las pérdidas acústicas en una celda acusto-óptica cristalina.

Los resultados de este análisis fueron confirmados primero en una celda acustoóptica

de molibdato de calcio (CaMoO4). Luego de esto, los resultados fueron

extrapolados para predecir el desempeño de una celda acusto-óptica de niobato de

litio (LiNbO3) encaminada a su aplicación en espectroscopía astrofísica cerca del

rango ultravioleta. Este material en particular, necesitó de un análisis más

profundo debido a fenómenos conocidos en él que podrían afectar las capacidades

de una celda de este material.

Después, la interacción acusto-óptica no colineal se estudió para el esparcimiento

multifonón de luz en el régimen de Bragg. Este régimen sólo permite dos posibles

casos, la interacción acusto-óptica de dos y de tres fonones. Junto con esto, un

grado de libertad específico de esta interacción acusto-óptica se introdujo para

regular la frecuencia acústica necesaria para que ocurra la interacción. El

esparcimiento multifonón de luz se analizó teoréticamente en dos cristales

diferentes; cloruro de mercurio (Hg2Cl2) para el caso de la interacción de dos

fonones y dióxido de telurio (TeO2) para el caso de tres fonones.

Doctoral thesis

Acousto-optical effects Non-linear acousto-optics Acousto-optical filters Multi-phonon light scattering CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Construcción de un espectrómetro Acusto-Óptico

GUILLERMO HERRERA MARTINEZ (2010)

La astronomía milimétrica y submilimétrica ha tomado relevancia en los últimos años

en la investigación dentro del Instituto Nacional de Astrofísica, Óptica y Electrónica

(INAOE). La construcción del Gran Telescopio Milimétrico (GTM), en colaboración

con la Universidad de Massachusetts (UMASS), ha traído como consecuencia la investigación

para el desarrollo de nuevas tecnologías de manufactura y desarrollo de nuevos

instrumentos para la investigación en esta área de la astrofísica.

La instalación de un radiotelescopio con una antena de 5 m de diámetro (RT5), en

el sitio de Sierra Negra, mismo donde se ha instalado GTM, nos da la oportunidad

de diseñar, analizar e implementar instrumentación en esta banda del espectro

electromagnético.

La espectroscopía en radiofrecuencias es una herramienta fundamental para el estudio

de objetos astronómicos en la banda de las microondas, típicamente ubicada entre 30

y 300 GHz, tales como máseres y ráfagas solares. Para ello es necesario el diseño y

construcción de instrumentos con alta resolución espectral de bajo consumo de potencia

y con dimensiones lo más compactas posibles que faciliten su manejo, transporte y

acoplamiento al telescopio.

Desde que Lambert [13] sugirió el uso del efecto acusto-óptico para el análisis espectral

en radiofrecuencias, se han visto grandes progresos tanto teóricos como experimentales

en el desarrollo de materiales acusto-ópticos, materiales piezo-eléctricos a altas frecuencias,

módulos láser de bajo consumo de energía y lentes. La conjunción de estos

avances han hecho más fácil la implementación de instrumentos de este tipo.

Los espectrómetros acusto-ópticos han mostrado claras ventajas tanto en consumo de

energía como en fácil manejo y transporte, razones principales por las que se han implementado

en telescopios espaciales tales como SWAS [11] y HERSCHEL [5], y la

tecnología involucrada está en constante desarrollo.

Este trabajo presenta los primeros resultados de una versión de laboratorio como primer

etapa para la construcción de un espectrómetro acusto-óptico. Se analizan las características

individuales de las componentes ópticas y electrónicas así como los resultados

en conjunto.

Master thesis

Spectrometer Acousto-optical deflections Radio applications CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ASTRONOMÍA Y ASTROFÍSICA

Designing the prototype of acousto-optic processor for astrophysical applications

ANA VIRGINIA HANESSIAN DE LA GARZA (2012)

The development of a new instrument is presented in this thesis. It will serve

as a perspective prototype able to estimate the performance of their applications

for practical measurements in astronomical spectroscopy covering from visible

to near infrared range. A very obvious advantage of this arrangement is the relative schematic simplicity due to the absence of any large aperture components.

Another important advantage, is the possibility of change the spectral range and

the resolution using only one dispersing element, that will increase the efficiency

of the observing time.

The system is a prototype of the triple product processor and it produce the

folded spectrum, accumulating advantages of both space and time integrating.

Separately, the space integrating gives a wide frequency bandwidth together

with relatively low frequency resolution, while the time integration provides a

high resolution for spectrum components accompanied by comparably narrow

frequency bandwidth. The processor is able to provide really high frequency

resolution, with a wide frequency bandwidth.

The main attention is paid to the time-bandwidth product, because just this

parameter can be taken as the most general one for the characterization of performance data inherent in each individual cell. Both the theoretical estimations

and the experimental data obtained for a large-aperture acousto-optical cell

based on a tellurium dioxide crystal, exploiting the anomalous light scattering,

gives the time-bandwidth product equal to about 4000.

The problem of optimizing the profile for the incident light beam has been studied. The need light-beam apodization, suppressing side lobes within registration

of each individual resolvable spot and increasing the dynamic range, can be realized using a multi-prism beam expander. It has been shown that the dynamic

range of about 40 dB in an optical system can be achieved.

En esta tesis se presenta el prototipo de un nuevo instrumento. Este nos dar

una perspectiva para estimar el rendimiento en aplicaciones para espectroscopia

astronómica cubriendo un rango desde el visible hasta el cercano infrarrojo. Las

ventajas de este arreglo esquemático son la relativa simplicidad debido a la

ausencia de componentes de mucha apertura y la posibilidad de cambiar el rango

espectral y la resolución usando solo un elemento dispersivo que incrementaría la

eficiencia en el tiempo de observación.

El sistema es un prototipo del procesador de triple producto que acumula las

ventajas de la integración tiempo y espacio. Por separado, la integración en

el espacio provee de un amplio ancho de banda en la frecuencia, pero relativamente baja resolución. Mientras que la integración en el tiempo provee una alta

resolución para componentes del espectro acompañado con un estrecho ancho de

banda. Este procesador es capaz de proveer una alta resolución con un amplio

ancho de banda.

Se presta mayor atención al producto tiempo-ancho de banda, puesto que este

parámetro puede nos habla del rendimiento inherente de cada celda. Se estudian

los regímenes de dispersión de la luz normal o anómala. Tanto las estimaciones

teóricas como experimentales muestran que los datos obtenidos para una celda

acusto-optica de dióxido de telurio de gran apertura en el régimen de dispersión

de la luz anómala dan un producto tiempo-ancho de banda igual a 4000.

Se estudia el problema de optimización del perfil del haz de luz incidente. La

necesidad de apodizar el haz incidente de luz, suprimiendo los lóbulos secundarios

sin registrar cada punto que se puede resolver y además incrementar el rango

dinámico, se puede obtener utilizando un expansor de múltiples prismas. Se

muestra que se puede alcanzar un rango dinámico de alrededor de 40 dB en un

sistema óptico.

Master thesis

Acousto-optical signal processing Two dimensional spectroscopy CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA ASTRONOMÍA Y ASTROFÍSICA

Direct multi-channel optical spectrum analysis of radio-wave signals using collinear wave heterodyning in the single acousto-optical cell

Alexander Shcherbakov DANIEL SANCHEZ LUCERO ABRAHAM LUNA CASTELLANOS (2010)

An attempt is made to improve the accuracy of a multi-channel parallel acousto-optical spectrum analysis through involving an additional nonlinear conversion into data processing. For this purpose we investigate the potential of exploiting a co-directional collinear wave heterodyning within an analysis of ultra-high-frequency radio-wave signals. The wave heterodyning under the proposal is performed via mixing the longitudinal elastic waves of finite amplitudes. It leads to a two-cascade processing in the single-crystalline cell and makes it possible to improve the relative frequency resolution of the acousto-optical spectrum analysis by an order of magnitude at the same frequency range. Both the theoretical findings and the corresponding estimations were used in proof-of-principle experiments directed at creating a new type of acousto-optical cell. The general concept of the proposed method and the basic conclusions are confirmed by experiments with the developed acousto-optic cell made of a lead molybdate crystal.

Article

Acousto-optical spectrum analysis Frequency resolution Collinear wave heterodyning CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA ÓPTICA

Acousto-optical spectrum analysis of ultra-high-frequency radio-wave analogue signals with an improved resolution exploiting the collinear acoustic wave heterodyning

ALEXANDER SHCHERBAKOV ABRAHAM LUNA CASTELLANOS DANIEL SANCHEZ LUCERO (2010)

This article is devoted to the problem of improving the frequency resolution inherent in a parallel acousto-optical spectrum analysis via involving an additional nonlinear phenomenon into the data processing. In so doing, we examine possible application of the wave heterodyning to the real-time scale acousto-optical analysis of the frequency spectrum belonging to ultra-high-frequency radio-wave signals peculiar, for example, for radio-astronomy. The nonlinear process of wave heterodyning is realized through providing a co-directional collinear interaction of the longitudinal acoustic waves of finite amplitudes. This process, which is beforehand studied theoretically and investigated experimentally via the acousto-optical technique as well, allows us either to improve the frequency resolution of spectrum analysis at a given frequency range or to increase by a few times the current frequencies of radio-wave signals under processing. The first step along this way is connected with the experimental modeling of the acoustic wave heterodyning in solids via exploitation of the specific acousto-optical cell based on a liquid, which allows the simplest realization of a cell with the needed properties. Then, these theoretical and practical findings are used in our experimental studies aimed at creating a new type of acousto-optical cells, which are able to improve the resolution inherent in acousto-optical spectrum analyzer operating over ultra-high-frequency radio-wave signals. In particular, the possibility of upgrading the frequency resolution through the acoustic wave heterodyning is experimentally demonstrated using the cell made of lead molybdate crystal. The obtained results demonstrate practical efficiency of

the novel approach presented.

Article

Acousto-optical spectrum analysis Waves of the finite amplitude Collinear wave heterodyning CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Application of acousto-optical interactions in crystals to performing the spectrum analysis of radio-signals and shaping the multi-wave coupled states

SANDRA ELOISA BALDERAS MATA (2008)

Acoustic waves were studied extensively in the 19th century; surface acoustic waves were first described by Lord Rayleigh in 1885 as they pertained to earthquakes [1]. The acousto-optical effect was first studied or predicted by Brillouin in 1922 [2]. Physically, this effect describes the interaction between light and sound waves. This interaction produces the diffraction of light from the medium which was first perturbed by an acoustic wave. Later, in 1932 Debye and Sears [3] and Lucas and Biquard [4] verified it experimentally when optical sources of sufficiently high coherence become available. Surprisingly, a large number of diffracted orders were observed, symmetrically spaced about the undiffracted beam. Brillouin proposed that this effect was due to rescattering of light from the acoustic beam, it was quantified until a theoretical treatment using Feynman diagrams was presented in 1980 by Korpel and Poon [5]. This established a rigorous physical description of the multiple scattering of plane waves; a similar concept had been employed in a mathematical formalism first presented in 1960 [6].

The presence of multiple diffracted orders was first explained in a classic series of papers by Raman and Nath in 1935-1936 [7], who modeled the sound column as a phase grating acting in transmission to give rise to many diffracted orders by interference. They also considered the problem of oblique and arbitrary angle of incidence of light on the acoustic beam. Debye and Sears [3], who also derived a criteria for single- and multiple-order diffraction phenomena (Debye-Sears ratio).

Doctoral thesis

Acousto-optical deflectos Spectrometers Nonlinear optics CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

Frequency bandwidth and potential resolution of optical modulators exploiting amulti-phonon lights cattering in crystals

ALEXANDER SHCHERBAKOV EDUARDO TEPICHIN RODRIGUEZ (2009)

We consider physical conditions for realizing the Bragg regime of one-, two-, and three-phonon scattering of light in optically anisotropic crystalline materials. The exact and closed analytical models for describing these regimes are developed and solved. The performed analysis takes into account an opportunity of realizing 100% efficiency of light scattering in these regimes. Possible applications lie in the fields of creating large-aperture modulators of light. In connection with this, the problems of optimizing the frequency bandwidths and potential resolution of such modulators are studied. Reasonable attention is paid to the contribution of acoustic anisotropy to frequency bandwidth. The analytical results are illustrated by computer simulations and compared with proof-of-principle experimental data related to a multi- phonon light scattering in a tellurium dioxide crystal.

Article

Non-collinear acousto-optical interaction in crystals Multi-phonon light scattering CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA

DESIGN, FABRICATION AND CHARACTERIZATION OF NONLINEAR PHOTONIC CRYSTAL FIBERS FOR NEAR INFRARED WAVELENGTH SUPERCONTINUUM LIGHT SOURCES

CARLOS ENRIQUE PORRAS BARAJAS (2017)

"In this work, all the stages at fabrication of HNL PCFs are carried out, starting from PCF design at using of special relations and finishing to HNL PCF fabrication. Once the fiber is made, it is necessary to characterize it. Some of the most important parameters are dispersion, attenuation, beam divergence and numerical aperture.

We present the appropriate way to compute the parameters and then to fabricate of the calculated HNL PCFs. Finally we expose the relevance of the design and fabrication of HNL for specific applications such as supercontinuum generation."

Master thesis

SUPERCONTINUUM GENERATION, PHOTONIC CRYSTAL FIBER, OPTICAL FIBER, NONLINEAR EFFECTS CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA ÓPTICA OPTICA NO LINEAL