Esta investigación está patrocinada por los EE.UU. Defense Advanced Research Projects Agency en Centros de Investigación de Ingeniería Fotónica Integrada (cifra) programa con el Dr. J. Scott Rodgers como gerente del proyecto. La información proporcionada en este informe no refleja necesariamente la posición o la política del gobierno de EE.UU. y ningún patrocinio oficial reales.

1. Preparación de microesferas PDMS (Esfera I) <ol><li> Polidimetilsiloxano (PDMS) de base y el agente de curado se mezclan con una relación en volumen de 60:1. </li><li> Una hebra de fibra óptica de sílice, aproximadamente 2 cm de largo, es primero despojado de su revestimiento de plástico utilizando un separador óptico. </li><li> Un extremo de la fibra se calienta y se estira para proporcionar un extremo de vástago que es ~ 25-50 micras de diámetro en la punta. </li><li> El extremo estirado de la fibra se sumerge en la mezcla de PDMS por una longitud de aproximadamente 2-4 mm y luego se retiró. </li><li> La tensión superficial y el peso de la mezcla de PDMS permitir la formación de una esfera en la punta de la fibra de sílice. El tamaño de la esfera es controlada por la longitud de inmersión y la velocidad de extracción. Mediante la variación de estos dos parámetros, diámetros de esfera en el rango de 100 micras - 1.000 micras se puede conseguir. </li><li> El conjunto de microesferas / vástago se coloca a continuación en un horno a ~ 90 ° C durante 4 horas para permitir el curado adecuado de la polimaterial de mer (para formar reticulados cadenas). Figura 1a es una vista esquemática de I. Esfera </li></ol> 2. PDMS basado triple capa Preparación Esfera (Sphere II) <ol><li> Una microesfera 60:1 PDMS se utiliza como el núcleo interno. Los mismos pasos descritos anteriormente en 1) es seguido por este proceso. </li><li> Una mezcla de titanato de bario (BaTiO 3) nano-partículas y PDMS 60:1 se utiliza como la capa media. La mezcla de PDMS, preparada de la misma manera descrita en 1,1) anteriormente, se mezcla con titanato de bario nano-partículas. </li><li> El núcleo de microesferas de PDMS se describe en 2,1) se sumerge en la mezcla de titanato de bario-PDMS para cubrirlo (con un espesor de capa nominal de ~ 10 m). </li><li> A continuación, el ámbito de dos capas se coloca en un horno a ~ 90 ° C durante 4 horas para permitir un curado adecuado de la segunda capa. </li><li> Una vez que la esfera de dos capas se cura, de nuevo se sumerge en una mezcla 60:1 de PDMS para proporcionar un recubrimiento exterior (tercera capa). Este extremocapa sirve como guía esférica óptica (~ 10 m de espesor). Figura 1b es un esquema de Sphere II. </li></ol> 3. Sílice / PDMS Preparación de microesferas (Esfera III) <ol><li> Una sección ~ 3 cm de largo de una fibra de sílice modo óptico único está primero despojado de su memoria intermedia (de plástico) de recubrimiento y, a continuación su punta se funde utilizando un micro-soplete (junto con el revestimiento y el núcleo). La tensión superficial y la gravedad trabajar juntos para dar forma a la punta fundida en una esfera. Esferas con diámetros que van desde 200 hasta 500 micras se puede conseguir con este proceso. </li><li> La microesfera de sílice se sumerge en un baño de PDMS base (sin el agente de curado) para cubrirlo con una capa de aproximadamente 50 micras. Esta capa externa permanece como una muy viscosos Bingham (rendimiento-estrés) de líquido. Figura 1c es un esquema de Esfera III. </li></ol> 4. Preparación de la fibra óptica <ol><li> Una sección de una fibra óptica de modo único es despojado de su cla plásticodding utilizando un separador óptico. Utilizando un micro-soplete la sección rayada de la fibra se calienta hasta que se funde (tanto el revestimiento y núcleo de la fibra). </li><li> Mientras que la sección central es fundido, un extremo de la fibra óptica se tira a lo largo de su eje para formar una sección cónica de la fibra que es de alrededor de 1 cm de largo. La duración del calentamiento, la velocidad de tracción y la distancia de determinar el diámetro de la sección cónica que oscila entre 10 y 20 micras. La luz del láser DFB está acoplado a la esfera a través de la sección cónica de la fibra. Figura 2 muestra el acoplamiento de esfera fibra. </li></ol> 5. Optoelectrónicos de configuración <ol><li> La salida de un láser DFB sintonizable está acoplado a una fibra óptica de modo único en un extremo y termina en un fotodiodo rápido en el otro extremo, como se muestra en la Figura 3. </li><li> La salida del fotodiodo se digitalizan mediante un convertidor analógico-a-digital (A / D) y se almacena en un ordenador personal (PC). </li><li&gt; Uso de una etapa de micro-traducción de la microesfera (tipo I, II o III) se pone en contacto con la sección cónica de la fibra óptica (Figuras 2 y 3) para proporcionar un acoplamiento óptico entre los dos elementos. </li><li> El láser DFB está sintonizado por un controlador de láser. El controlador de láser, a su vez, es accionado por un generador de función que proporciona una entrada de tensión de diente de sierra. </li></ol> 6. Generación de Campo Eléctrico <ol><li> Dos placas de latón cuadrados (2 x 2 cm) con un espesor de 1 mm se utilizan para generar el campo eléctrico uniforme. Las placas están conectadas a una fuente de tensión y los sensores de esfera se colocan en el hueco entre las dos placas (Figura 4). </li><li> Con el fin de aumentar la sensibilidad de la medida, las esferas se primera polarizado en un campo eléctrico de 1 MV / m durante 2 horas. </li></ol>

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V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Wall+shear+stress+sensor+based+on+the+optical+resonances+of+dielectric+microspheres.">Wall shear stress sensor based on the optical resonances of dielectric microspheres.</a> Measurement science and technology. 22, 075203 (2011).</li><li>Ioppolo, T., Ayaz, U. K., &#214;t&#252;gen, M. V. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Tuning+of+whispering+gallery+modes+of+spherical+resonators+using+an+external+electric+field.">Tuning of whispering gallery modes of spherical resonators using an external electric field.</a> Optics express. 17 (19), 16465-16479 (2009).</li><li>Ioppolo, T., Stubblefield, J., &#214;t&#252;gen, M. 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No tenemos nada que revelar.

Las esferas están inicialmente polarizada mediante la conexión de los electrodos a una fuente de alta tensión continua. Al final de la duración de polarización, los cables de los electrodos se desconecta de la fuente de tensión de CC y conectado a un generador de funciones, como se indica en la Figura 4. Los resultados presentados en las figuras 5 a 8 muestran que los campos eléctricos positivos y negativos (con respecto a la dirección de polarización) conducen...

<table border="1"><tbody><tr><td></td><td> Empresa </td><td> Número de catálogo </td><td> Comentarios (opcional) </td></tr><tr><td> PDMS </td><td> Dow Corning </td><td> Sylgard 184 </td><td></td></tr><tr><td> Fibra de sílice </td><td> Las ventas de fibra de instrumentos </td><td> E-37AP15-FIS </td><td></td></tr><tr><td> Titanato de bario (BaTiO3) nanopartículas </td><td> Sigma Aldrich </td><td> 467634-100G </td><td></td></tr><tr><td> Laser Controller </td><td> ILX Lightwave </td><td> LDC-3724B </td><td></td></tr><tr><td> Láser DFB </td><td> Agere </td><td> Agere 2300 </td><td> Longitud de onda central 1,310 micras </td></tr><tr><td> Photodiode </td><td> Thorlabs </td><td> PDA10CS </td><td></td></tr><tr><td> A / D Tarjeta </td><td> National Instruments </td><td> PXI 6115 </td><td></td>
 </tr>
 </tbody>
</table>

development of whispering gallery mode polymeric micro-optical electric field sensors

Modos ópticos dieléctricos de micro-cavidades han recibido mucha atención en los últimos años por su potencial en una amplia gama de aplicaciones. Los modos ópticos se refiere con frecuencia como &quot;susurro modos Gallery&quot; (WGM) o &quot;resonancias morfológicas dependientes&quot; (MDR) y muestran altos factores de calidad óptica. Algunas aplicaciones propuestas de micro-cavidad resonadores ópticos son en espectroscopia 1, micro-cavidad tecnología láser 2, comunicaciones ópticas 3-6, así como la tecnología de sensor. Las aplicaciones de sensores basados ​​en WGM incluyen aquellos en biología 7, detección de rastros de gas 8, y la detección de impurezas en líquidos 9. Sensores mecánicos basados ​​en resonadores de microesferas también han sido propuestas, incluyendo aquellos para la fuerza de 10,11, 12 de presión, aceleración 13 y la tensión de cizallamiento 14. En la actualidad, se demuestra un sensor basado en WGM campo eléctrico, que se basa en nuestra studi anteriores 15,16. Una aplicación candidato de este sensor es en la detección de potencial de acción neuronal. El sensor de campo eléctrico está basado en microesferas poliméricas multicapa dieléctrico. El campo eléctrico externo induce la superficie y las fuerzas del cuerpo en las esferas (efecto electrostricción) que conducen a la deformación elástica. Este cambio en la morfología de las esferas, conduce a cambios en la WGM. El campo eléctrico inducido cambios WGM son interrogados por los emocionantes modos ópticos de las esferas de luz láser. La luz de una realimentación distribuida (DFB) láser (longitud de onda nominal de ~ 1,3 micras) es de lado acoplado en las microesferas usando una sección ahusada de una fibra de modo óptico único. El material de base de las esferas es el polidimetilsiloxano (PDMS). Tres geometrías de microesferas se utiliza: (1) esfera PDMS con una relación volumétrica 60:1 de base-a-curado mezcla de agente, (2) la esfera de múltiples capas con 60:1 PDMS núcleo, con el fin de aumentar la constante dieléctrica del the esfera, una capa intermedia de 60:1 de PDMS que se mezcla con cantidades variables (2% a 10% en volumen) de titanato de bario y una capa externa de 60:1 PDMS y (3) la esfera de sílice sólida revestida con una capa delgada de base de PDMS sin curar. En cada tipo de sensor, la luz láser de la fibra cónica se acopla a la capa más externa que proporciona alta calidad óptica factor de WGM (Q ~ 10 6). Las microesferas se polariza durante varias horas a campos eléctricos de ~ 1 MV / m para aumentar su sensibilidad al campo eléctrico.

Un modo óptico (WGM) de la esfera es excitado por la luz de láser cuando la longitud del camino óptico recorrido por la luz es un múltiplo entero de la longitud de onda del láser. Para la disposición mostrada en la Figura 3, la longitud del camino óptico es 2πrn, donde n y r son el índice de refracción y el radio de la esfera, respectivamente. Usando la aproximación de la óptica geométrica, una condición WGM se satisface cuando 2πrn = lλ donde l</e...

Watch this Scientific Journal Video about Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors at JoVE.com

Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors

Un sensor de micro de alta sensibilidad fotónica fue desarrollado para la detección de campo eléctrico. El sensor explota los modos ópticos de una esfera dieléctrica. Los cambios en el campo eléctrico externo perturbar la morfología esfera que conduce a cambios en sus modos ópticos. La intensidad de campo eléctrico se mide mediante el control de estos cambios ópticos.

Desarrollo de la Whispering Gallery Mode poliméricos micro-ópticos Sensores de campos eléctricos

Optical modes of dielectric micro-cavities have received significant attention in recent years for their potential in a broad range of applications. The ...

development-whispering-gallery-mode-polymeric-micro-optical-electric

Research

JoVE Journal

Engineering

13.0K vistas.  Southern Methodist University. Un sensor de micro de alta sensibilidad fotónica fue desarrollado para la detección de campo eléctrico. El sensor explota los modos ópticos de una esfera dieléctrica. Los cambios en el campo eléctrico externo perturbar la morfología esfera que conduce a cambios en sus modos ópticos. La intensidad de campo eléctrico se mide mediante el control de estos cambios ópticos.

Video: Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors

Microwave Photonics Systems Based on Whispering-gallery-mode Resonators

Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various areas of technology and applied science, such as aerospace and communication engineering, sensing, metrology, nonlinear photonics, and quantum optics. In this article, we present the principal techniques used in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators. First detailed in this article is the protocol for resonator polishing, which is based on a grind-and-polish technique close to the ones used to polish optical components such as lenses or telescope mirrors. Then, a white light interferometric profilometer measures surface roughness, which is a key parameter to characterize the quality of the polishing. In order to launch light in the resonator, a tapered silica fiber with diameter in the micrometer range is used. To reach such small diameters, we adopt the "flame-brushing" technique, using simultaneously computer-controlled motors to pull the fiber apart, and a blowtorch to heat the fiber area to be tapered. The resonator and the tapered fiber are later approached to one another to visualize the resonance signal of the whispering gallery modes using a wavelength-scanning laser. By increasing the optical power in the resonator, nonlinear phenomena are triggered until the formation of a Kerr optical frequency comb is observed with a spectrum made of equidistant spectral lines. These Kerr comb spectra have exceptional characteristics that are suitable for several applications in science and technology. We consider the application related to ultra-stable microwave frequency synthesis and demonstrate the generation of a Kerr comb with GHz intermodal frequency.

The customized techniques developed in our lab to build microwave photonics systems based on ultra-high Q whispering gallery mode resonators are presented. The protocols to obtain and characterize these resonators are detailed, and an explanation of some of their applications in microwave photonics is given.

Microondas Fotónica sistemas basados ​​en resonadores-gallery-mode Whispering

Microwave photonics systems rely fundamentally on the interaction between microwave and optical signals. These systems are extremely promising for various ...

Investigación

Ingeniería

Real-Time DC-dynamic Biasing Method for Switching Time Improvement in Severely Underdamped Fringing-field Electrostatic MEMS Actuators

Mechanically underdamped electrostatic fringing-field MEMS actuators are well known for their fast switching operation in response to a unit step input bias voltage. However, the tradeoff for the improved switching performance is a relatively long settling time to reach each gap height in response to various applied voltages. Transient applied bias waveforms are employed to facilitate reduced switching times for electrostatic fringing-field MEMS actuators with high mechanical quality factors. Removing the underlying substrate of the fringing-field actuator creates the low mechanical damping environment necessary to effectively test the concept. The removal of the underlying substrate also a has substantial improvement on the reliability performance of the device in regards to failure due to stiction. Although DC-dynamic biasing is useful in improving settling time, the required slew rates for typical MEMS devices may place aggressive requirements on the charge pumps for fully-integrated on-chip designs. Additionally, there may be challenges integrating the substrate removal step into the back-end-of-line commercial CMOS processing steps. Experimental validation of fabricated actuators demonstrates an improvement of 50x in switching time when compared to conventional step biasing results. Compared to theoretical calculations, the experimental results are in good agreement.

The robust device design of fringing-field electrostatic MEMS actuators results in inherently low squeeze-film damping conditions and long settling times when performing switching operations using conventional step biasing. Real-time switching time improvement with DC-dynamic waveforms reduces the settling time of fringing-field MEMS actuators when transitioning between up-to-down and down-to-up states.

Real-Time DC-dinámico Método de polarización de conmutación Tiempo Mejoras en Severamente Subamortiguado Fleco campo electrostático MEMS actuadores

Mechanically underdamped electrostatic fringing-field MEMS actuators are well known for their fast switching operation in response to a unit step input ...

Characterization of Anisotropic Leaky Mode Modulators for Holovideo

Holovideo displays are based on light-bending spatial light modulators. One such spatial light modulator is the anisotropic leaky mode modulator. This modulator is particularly well suited for holographic video experimentation as it is relatively simple and inexpensive to fabricate1-3. Some additional advantages of leaky mode devices include: large aggregate bandwidth, polarization separation of signal light from noise, large angular deflection and frequency control of color1. In order to realize these advantages, it is necessary to be able to adequately characterize these devices as their operation is strongly dependent on waveguide and transducer parameters4. To characterize the modulators, the authors use a commercial prism coupler as well as a custom characterization apparatus to identify guided modes, calculate waveguide thickness and finally to map the device's frequency input and angular output of leaky mode modulators. This work gives a detailed description of the measurement and characterization of leaky mode modulators suitable for full-color holographic video.

This work describes fabrication and characterization of anisotropic leaky mode modulators for holographic video.

Caracterización de anisotrópico de modo que gotean moduladores para holovídeo

Holovideo displays are based on light-bending spatial light modulators.  One such spatial light modulator is the anisotropic leaky mode modulator.  This ...

Stimulated Stokes and Antistokes Raman Scattering in Microspherical Whispering Gallery Mode Resonators

Dielectric microspheres can confine light and sound for a length of time through high quality factor whispering gallery modes (WGM). Glass microspheres can be thought as a store of energy with a huge variety of applications: compact laser sources, highly sensitive biochemical sensors and nonlinear phenomena. A protocol for the fabrication of both the microspheres and coupling system is given. The couplers described here are tapered fibers. Efficient generation of nonlinear phenomena related to third order optical non-linear susceptibility &#935;(3) interactions in triply resonant silica microspheres is presented in this paper. The interactions here reported are: Stimulated Raman Scattering (SRS), and four wave mixing processes comprising Stimulated Anti-stokes Raman Scattering (SARS). A proof of the cavity-enhanced phenomenon is given by the lack of correlation among the pump, signal and idler: a resonant mode has to exist in order to obtain the pair of signal and idler. In the case of hyperparametric oscillations (four wave mixing and stimulated anti-stokes Raman scattering), the modes must fulfill the energy and momentum conservation and, last but not least, have a good spatial overlap.

Efficient generation of nonlinear phenomena related to third order optical non-linear susceptibility &#935;(3) interactions in triply resonant silica microspheres is presented in this paper. The interactions here reported are: Stimulated Raman Scattering (SRS), and four wave mixing processes comprising Stimulated Anti-stokes Raman Scattering (SARS).

Estimulada Stokes y Antistokes Raman Scattering en microesférico Whispering Gallery Mode resonadores

Dielectric microspheres can confine light and sound for a length of time through high quality factor whispering gallery modes (WGM). Glass microspheres ...

Fiber Optic Distributed Sensors for High-resolution Temperature Field Mapping

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists chiefly of velocity and temperature readings, both ideally having high spatial and temporal resolution to facilitate rigorous code validation. While high resolution velocity data is readily obtained through optical measurement techniques such as particle image velocimetry, it has proven difficult to obtain temperature data with similar resolution. Traditional sensors such as thermocouples cannot fill this role, but the recent development of distributed sensing based on Rayleigh scattering and swept-wave interferometry offers resolution suitable for CFD code validation work. Thousands of temperature measurements can be generated along a single thin optical fiber at hundreds of Hertz. Sensors function over large temperature ranges and within opaque fluids where optical techniques are unsuitable. But this type of sensor is sensitive to strain and humidity as well as temperature and so accuracy is affected by handling, vibration, and shifts in relative humidity. Such behavior is quite unlike traditional sensors and so unconventional installation and operating procedures are necessary to ensure accurate measurements. This paper demonstrates implementation of a Rayleigh scattering-type distributed temperature sensor in a thermal mixing experiment involving two air jets at 25 and 45 &#176;C. We present criteria to guide selection of optical fiber for the sensor and describe installation setup for a jet mixing experiment. We illustrate sensor baselining, which links readings to an absolute temperature standard, and discuss practical issues such as errors due to flow-induced vibration. This material can aid those interested in temperature measurements having high data density and bandwidth for fluid dynamics experiments and similar applications. We highlight pitfalls specific to these sensors for consideration in experiment design and operation.

We demonstrate use of a fiber optic distributed sensor for mapping the temperature field of mixing air jets. The Rayleigh scattering-based sensor generates thousands of data points along a single fiber to provide exceptional spatial resolution that is unattainable with traditional sensors such as thermocouples.

De fibra óptica para sensores distribuidos de alta resolución de mapeo de temperatura Campo

The reliability of computational fluid dynamics (CFD) codes is checked by comparing simulations with experimental data. A typical data set consists ...

Nanostructured Ag-zeolite Composites as Luminescence-based Humidity Sensors

Small silver clusters confined inside zeolite matrices have recently emerged as a novel type of highly luminescent materials. Their emission has high external quantum efficiencies (EQE) and spans the whole visible spectrum. It has been recently reported that the UV excited luminescence of partially Li-exchanged sodium Linde type A zeolites [LTA(Na)] containing luminescent silver clusters can be controlled by adjusting the water content of the zeolite. These samples showed a dynamic change in their emission color from blue to green and yellow upon an increase of the hydration level of the zeolite, showing the great potential that these materials can have as luminescence-based humidity sensors at the macro and micro scale. Here, we describe the detailed procedure to fabricate a humidity sensor prototype using silver-exchanged zeolite composites. The sensor is produced by suspending the luminescent Ag-zeolites in an aqueous solution of polyethylenimine (PEI) to subsequently deposit a film of the material onto a quartz plate. The coated plate is subjected to several hydration/dehydration cycles to show the functionality of the sensing film.

A protocol for the synthesis of moisture-responsive luminescent Ag-zeolite composites is described in this report.

Compuestos nanoestructurados Ag-zeolita como sensores de humedad basados ​​en luminiscencia

Small silver clusters confined inside zeolite matrices have recently emerged as a novel type of highly luminescent materials. Their emission has high ...

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating

A method of carrier number control by electrolyte gating is demonstrated. We have obtained WS2 thin flakes with atomically flat surface via scotch tape method or individual WS2 nanotubes by dispersing the suspension of WS2 nanotubes. The selected samples have been fabricated into devices by the use of the electron beam lithography and electrolyte is put on the devices. We have characterized the electronic properties of the devices under applying the gate voltage. In the small gate voltage region, ions in the electrolyte are accumulated on the surface of the samples which leads to the large electric potential drop and resultant electrostatic carrier doping at the interface. Ambipolar transfer curve has been observed in this electrostatic doping region. When the gate voltage is further increased, we met another drastic increase of source-drain current which implies that ions are intercalated into layers of WS2 and electrochemical carrier doping is realized. In such electrochemical doping region, superconductivity has been observed. The focused technique provides a powerful strategy for achieving the electric-filed-induced quantum phase transition.

Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating

Here, we present a protocol to control the carrier number in solids by using the electrolyte.

Campo eléctrico Control de Estados electrónicos en WS2 nanodispositivos de electrolito que bloquean

A method of carrier number control by electrolyte gating is demonstrated. We have obtained WS2 thin flakes with atomically flat surface via scotch tape ...

Ultrasonic Fatigue Testing in the Tension-Compression Mode

Ultrasonic fatigue testing is one of a few methods which allow investigating fatigue properties in the ultra-high cycle region. The method is based on exposing the specimen to longitudinal vibrations on its resonance frequency close to 20 kHz. With use of this method, it is possible to significantly decrease the time required for the test, when compared to conventional testing devices usually working at frequencies under 200 Hz. It is also used to simulate loading of material during operation in high speed conditions, such as those experienced by components of jet engines or car turbo pumps. It is necessary to operate only in the high and ultra-high cycle region, due to the possibility of extremely high deformation rates, which can have a significant influence on the test results. Specimen shape and dimensions have to be carefully selected and calculated to fulfill the resonance condition of the ultrasonic system; thus, it is not possible to test the full components or specimens of arbitrary shape. Before each test, it is necessary to harmonize the specimen with the frequency of the ultrasonic system to compensate for deviations of the real shape from the ideal one. It is not possible to run a test until a total fracture of the specimen, since the test is automatically terminated after initiation and propagation of the crack to a certain length, when the stiffness of the system changes enough to shift the system out of the resonance frequency. This manuscript describes the process of evaluation of materials' fatigue properties at high-frequency ultrasonic fatigue loading with use of mechanical resonance at a frequency close to 20 kHz. The protocol includes a detailed description of all steps required for a correct test, including specimen design, stress calculation, harmonizing with the resonance frequency, performing the test, and final static fracture.

A protocol for ultrasonic fatigue testing in the high and ultra-high cycle region in axial tension-compression loading mode.

Fatiga ultrasónica prueba en el modo de tensión-compresión

Ultrasonic fatigue testing is one of a few methods which allow investigating fatigue properties in the ultra-high cycle region. The method is based on ...

Radio Frequency Magnetron Sputtering of GdBa2Cu3O7&#8722;&#948;/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates

Here, we demonstrate a method of coating ferromagnetic La0.67Sr0.33MnO3 (LSMO) nanoparticles on (001) SrTiO3 (STO) single-crystal substrates by radio frequency (RF) magnetron sputtering. LSMO nanoparticles were deposited with diameters from 10 to 20 nm and heights between 20 and 50 nm. At the same time, (Gd) Ba2Cu3O7&#8722;&#948; ((Gd) BCO) films were fabricated on both undecorated and LSMO nanoparticle decorated STO substrates using RF magnetron sputtering. This report also describes the properties of GdBa2Cu3O7&#8722;&#948;/ La0.67Sr0.33MnO3 quasi-bilayer films structures (e.g., crystalline phase, morphology, chemical composition); magnetization, magneto-transport, and superconducting transport properties were also evaluated.

Radio Frequency Magnetron Sputtering of GdBa2Cu3O7ÃƒÂ¢Ã‹â€ &#039;ÃƒÅ½ ´/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 STO Single-crystal Substrates

Here, we present a protocol to grow LSMO nanoparticles and (Gd) BCO films on (001) SrTiO3 (STO) single-crystal substrates by radio frequency (RF)-sputtering.

Radio frecuencia de magnetrón Sputtering de GdBa2Cu3O7−δ/ La0.67Films Sr0.33MnO3 cuasi-bicapa sobre sustratos de monocristal SrTiO3 (STO)

Here, we demonstrate a method of coating ferromagnetic La0.67Sr0.33MnO3 (LSMO) nanoparticles on (001) SrTiO3 (STO) single-crystal substrates by radio ...

Hybrid Printing for the Fabrication of Smart Sensors

A method to combine additively manufactured substrates or foils and multilayer inkjet printing for the fabrication of sensor devices is presented. First, three substrates (acrylate, ceramics, and copper) are prepared. To determine the resulting material properties of these substrates, profilometer, contact angle, scanning electron microscope (SEM), and focused ion beam (FIB) measurements are done. The achievable printing resolution and suitable drop volume for each substrate are, then, found through the drop size tests. Then, layers of insulating and conductive ink are inkjet printed alternately to fabricate the target sensor structures. After each printing step, the respective layers are individually treated by photonic curing. The parameters used for the curing of each layer are adapted depending on the printed ink, as well as on the surface properties of the respective substrate. To confirm the resulting conductivity and to determine the quality of the printed surface, four-point probe and profilometer measurements are done. Finally, a measurement set-up and results achieved by such an all-printed sensor system are shown to demonstrate the achievable quality.

Here we present a protocol for the fabrication of inkjet-printed multilayer sensor structures on additively manufactured substrates and foil.

Híbrido de la impresión para la fabricación de sensores inteligentes

A method to combine additively manufactured substrates or foils and multilayer inkjet printing for the fabrication of sensor devices is presented. First, ...