Questa ricerca è sponsorizzato dalla US Defense Advanced Research Projects Agency sotto Centri in Integrated Photonics Engineering Research (cifrario) programma con il dottor J. Scott Rodgers come project manager. Le informazioni contenute in questa relazione non riflettono necessariamente la posizione o la politica del governo degli Stati Uniti e nessuna approvazione ufficiale può essere presupposta.

1. PDMS Microsfera Preparazione (Sphere I) <ol><li> Polidimetilsilossano (PDMS) base e l&#39;indurente sono miscelati con un rapporto in volume di 60:1. </li><li> Un filo di fibra ottica di silice, circa 2 cm di lunghezza, è prima spogliato del suo rivestimento in plastica con una spogliarellista ottico. </li><li> Una estremità della fibra è riscaldata e tesa a fornire un gambo che è ~ 25-50 micron di diametro di punta. </li><li> L&#39;estremità allungata della fibra è sommerso nella miscela PDMS da una lunghezza di circa 2-4 mm e quindi viene estratta. </li><li> Tensione superficiale e peso della miscela PDMS permettere la formazione di una sfera sulla punta della fibra di silice. La dimensione della sfera è controllata dalla lunghezza immersione e la velocità di estrazione. Variando questi due parametri, diametri sfera nell&#39;intervallo 100 pm - 1.000 micron può essere ottenuta. </li><li> Microsfera / stelo viene quindi posto in un forno a ~ 90 ° C per 4 ore per consentire indurimento corretto del polimateriale mer (per formare reticolati catene). figura 1a è uno schema di I. Sfera </li></ol> 2. PDMS-based Tripla Sfera Preparazione Layer (Sphere II) <ol><li> Un microsfere 60:1 PDMS è usato come il nucleo interno. Le stesse fasi descritte nella colonna 1) è seguita per questo processo. </li><li> Una miscela di titanato di bario (Batio 3) nano-particelle e 60:1 PDMS è utilizzato come strato intermedio. La miscela PDMS, preparato nello stesso modo descritto in 1.1) di cui sopra, viene miscelato con il titanato di bario nanoparticelle. </li><li> Il nucleo microsfere PDMS descritto in 2.1) viene quindi immerso nella miscela PDMS-titanato di bario a cappotto (con uno spessore nominale di ~ 10 um). </li><li> Successivamente, la sfera a due strati viene posto in un forno a ~ 90 ° C per 4 ore per consentire la corretta maturazione del secondo strato. </li><li> Una volta che la sfera due strati è indurito, esso viene nuovamente immerso in una miscela di 60:1 PDMS per fornire un rivestimento esterno (terzo strato). Il più esternostrato serve come guida ottica sferica (~ 10 um di spessore). Figura 1b è uno schema di Sphere II. </li></ol> 3. Silice / Preparazione Microsphere PDMS (Sphere III) <ol><li> A ~ 3 cm lunga sezione di una fibra ottica monomodo silice viene privata del suo primo buffer (plastica) rivestimento e quindi la sua punta viene fuso mediante un micro-torcia (insieme con il rivestimento e core). Tensione superficiale e la gravità lavorare insieme per modellare la punta fuso in una sfera. Sfere con diametro da 200 a 500 um può essere ottenuto con questo processo. </li><li> Il microsfere di silice viene poi immerso in un bagno di PDMS base (senza induritore) di coprire con una mano di ~ 50 pm. Questo strato esterno rimane come altamente viscoso Bingham (resa-stress) fluido. Figura 1c è uno schema di Sphere III. </li></ol> 4. Fibra ottica di preparazione <ol><li> Una sezione di una fibra ottica monomodale viene privato della cla plasticadding utilizzando un stripper ottico. Usando un micro-torcia sezione strisce della fibra viene riscaldata fino a quando è fuso (sia il rivestimento e nucleo della fibra). </li><li> Mentre la sezione centrale è fuso, una estremità della fibra ottica viene tirato lungo il suo asse per formare una sezione rastremata della fibra che è di circa 1 cm di lunghezza. La durata del riscaldamento, la velocità e la distanza tirando determinare il diametro della sezione conica che varia tra 10 e 20 micron. La luce del laser DFB viene accoppiato nella sfera attraverso la sezione rastremata della fibra. Figura 2 mostra la sfera fibra accoppiamento. </li></ol> 5. Optoelettronici Setup <ol><li> L&#39;uscita di un laser sintonizzabile DFB viene accoppiata in una fibra ottica monomodale su una estremità e chiuso in un fotodiodo veloce all&#39;altra estremità come mostrato in Figura 3. </li><li> L&#39;uscita fotodiodo viene digitalizzato mediante un convertitore analogico-a-digitale (A / D) e memorizzati su un personal computer (PC). </li><li&gt; Utilizzo di un micro-traduzione stadio microsfera (tipo I, II o III) viene portato in contatto con la sezione rastremata della fibra ottica (figure 2 e 3) per fornire accoppiamento ottico tra i due elementi. </li><li> Il laser DFB viene preparata da un controllore laser. Il controllore del laser, a sua volta azionato da un generatore di funzione che fornisce un dente di sega ingresso di tensione. </li></ol> 6. Campo di generazione elettrica <ol><li> Due lastre di ottone quadrato (2 x 2 cm) con spessore di 1 mm sono utilizzati per generare il campo elettrico uniforme. Le piastre sono collegate ad una alimentazione di tensione e la sfera sensori sono collocati nello spazio tra le due piastre (Figura 4). </li><li> Al fine di aumentare la sensibilità di misura, le sfere vengono prima polarizzato in un campo elettrico di 1 MV / m per 2 h. </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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Le sfere sono inizialmente polarizzato collegando gli elettrodi ad una elevata tensione di alimentazione DC. Alla fine della durata poling, i cavi elettrodi sono scollegati dalla tensione DC e collegato ad un generatore di funzione come indicato nella figura 4. I risultati presentati nelle figure da 5 a 8 mostrano che campi elettrici positivi e negativi (rispetto alla direzione di polarizzazione) portano a sfera allungamento e compressione, rispettivamente. I sfera, che...

<table border="1"><tbody><tr><td></td><td> Azienda </td><td> Numero di catalogo </td><td> Commenti (opzionale) </td></tr><tr><td> PDMS </td><td> Dow Corning </td><td> Sylgard 184 </td><td></td></tr><tr><td> Silica fibra </td><td> Fibra di strumenti di vendita </td><td> E-37AP15-FIS </td><td></td></tr><tr><td> Titanato di bario (Batio 3) nanoparticelle </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> DFB laser </td><td> Agere </td><td> Agere 2300 </td><td> Lunghezza d&#39;onda di 1,310 micron centrale </td></tr><tr><td> Fotodiodo </td><td> Thorlabs </td><td> PDA10CS </td><td></td></tr><tr><td> D / Scheda </td><td> National Instruments </td><td> PXI 6115 </td><td></td>
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development of whispering gallery mode polymeric micro-optical electric field sensors

Modi ottici dielettrici di micro-cavità hanno ricevuto notevole attenzione in anni recenti per il loro potenziale in una vasta gamma di applicazioni. I modi ottici sono spesso indicati come &quot;sussurrare modalità gallery&quot; (WGM) o &quot;risonanze morfologia dipendenti&quot; (MDR) e presentano elevati fattori di qualità ottica. Alcune applicazioni proposte di risonatori ottici micro-cavità sono in spettroscopia 1, micro-cavità tecnologia laser 2, comunicazioni ottiche 3-6 e sensori. I WGM applicazioni basate su sensori includono quelli in biologia 7, rilevazione di gas traccia 8, e la rilevazione impurità in liquidi 9. Sensori meccanici basati su risonatori microsfere sono anche state proposte, compresi quelli per forza 10,11, pressione 12, 13 e accelerazione parete sollecitazione di taglio 14. Nel presente, si dimostra un WGM-based sensore di campo elettrico, che si basa sulla nostra studi precedenties 15,16. Un&#39;applicazione candidato di questo sensore è nella rivelazione di potenziale d&#39;azione neuronale. Il sensore di campo elettrico si basa su polimerico multistrato dielettrico microsfere. Il campo elettrico esterno induce superficie e forze di massa sulle sfere (effetto electrostriction) che portano alla deformazione elastica. Questo cambiamento nella morfologia delle sfere, conduce a cambiamenti del WGM. Il campo elettrico indotto turni WGM sono interrogati dai emozionanti modi ottici delle sfere di luce laser. Luce da una retroazione distribuita (DFB) laser (lunghezza d&#39;onda nominale di ~ 1,3 um) è lato-accoppiato nel microsfere con una sezione rastremata di una fibra ottica monomodale. Il materiale di base delle sfere è polidimetilsilossano (PDMS). Tre geometrie microsfere vengono utilizzati: (1) PDMS sfera con un rapporto volumetrico 60:1 di base-a-curing miscela agente, (2) sfera multistrato con 60:1 PDMS nucleo, per aumentare la costante dielettrica the sfera, uno strato intermedio di 60:1 PDMS che viene miscelato con quantità variabili (2% al 10% in volume) di titanato di bario e uno strato esterno di 60:1 PDMS e (3) sfera silice solido rivestito con uno strato sottile di non polimerizzato base di PDMS. In ogni tipo di sensore, luce laser dalla fibra rastremata è accoppiata nello strato più esterno che fornisce alta qualità ottica fattore WGM (Q ~ 10 6). Le microsfere vengono polarizzato per diverse ore a campi elettrici di ~ 1 MV / m per aumentare la loro sensibilità al campo elettrico.

Un modo ottico (WGM) della sfera viene eccitato dalla luce laser quando la lunghezza del cammino ottico percorsa dalla luce è un multiplo intero della lunghezza d&#39;onda del laser. Per la disposizione mostrata in figura 3, la lunghezza del percorso ottico è 2πrn, dove n ed r sono l&#39;indice di rifrazione e il raggio della sfera, rispettivamente. Utilizzando geometrico approssimazione ottica, una condizione WGM è soddisfatta quando 2πrn = lλ dove l ?...

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 sensore ad alta sensibilità fotonici micro stato sviluppato per il rilevamento del campo elettrico. Il sensore sfrutta i modi ottici di una sfera dielettrica. Le variazioni del campo elettrico esterno turbare la morfologia sfera che porta a cambiamenti nei suoi modi ottici. L&#39;intensità del campo elettrico viene misurata monitorando questi spostamenti ottici.

Sviluppo di Whispering Galleria polimerici modalità micro-ottici sensori di campo elettrico

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

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13.0K Views.  Southern Methodist University. Un sensore ad alta sensibilità fotonici micro stato sviluppato per il rilevamento del campo elettrico. Il sensore sfrutta i modi ottici di una sfera dielettrica. Le variazioni del campo elettrico esterno turbare la morfologia sfera che porta a cambiamenti nei suoi modi ottici. L'intensità del campo elettrico viene misurata monitorando questi spostamenti ottici.

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.

Microonde Photonics sistemi basati su risonatori-galleria-mode Whispering

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

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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-dinamica Metodo di polarizzazione per il tempo di commutazione miglioramento Severamente sottosmorzato frangente campo elettrostatico MEMS Attuatori

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.

Caratterizzazione di anisotropi Leaky modalità modulatori per Holovideo

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).

Stimolata Stokes e Antistokes Raman Scattering in Microspherical Whispering Gallery modalità risonatori

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.

Fibre ottiche sensori distribuiti per alta risoluzione Mappatura 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.

Compositi nanostrutturati Ag-zeolite come Sensori di umidità a base di luminescenza

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.

Controllo campo elettrico degli stati elettronici in nanodispositivi2 WS di elettrolita 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 ...

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.

Prova in modalità trazione-compressione ad ultrasuoni di fatica

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 frequenza Magnetron Sputtering di GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 quasi-bilayer film su substrati di singolo-cristallo di 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.

Ibrido di stampa per la fabbricazione di sensori intelligenti

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