Particle shape and size determine the physicochemical optoelectronic properties of nanoscale materials, including optical absorption, fluorescence, electric magnetic moments. It is thus desirable to be able synthesize separate various particle shapes sizes. Biosynthesis using microorganisms has emerged as a more ecologically friendly, simpler, reproducible alternative chemical synthesis metal semiconductor nanoparticles, allowing generation rare forms such triangles. Here we show that plant...

Microelectromechanical system (MEMS) technology, and surface micromachining in particular, have led to the development of miniaturized optical devices with a substantial impact large number application areas. The reason is unique MEMS characteristics that are advantageous fabrication, systems integration, operation micro-optical systems. precision mechanics MEMS, microfabrication techniques, functionality all make possible wide variety movable tunable mirrors, lenses, filters, other...

We report a refractive index (RI) sensor based on the use of vertically etched silicon Bragg reflectors. The device is robust and performs measurements through tens micrometers liquid. A sensitivity 907 nm/RIU (RI units) resolution 1.7×10−5 RIU are obtained in good agreement with optical simulations. This highest reported for volume RI integrated microfluidic system. Expected applications fields single cell characterization chip liquid chromatography discussed.

In this paper, we present a novel optical microelectromechanical systems (MEMS) accelerometer sensor dedicated to space applications. An in-plane Fabry-Pérot (FP) microcavity (FPM) with two distributed Bragg reflectors (DBRs) is used detect the acceleration. One of DBR mirrors attached suspended proof masses, allowing FP gap change while masses experience Acceleration then detected by measuring spectral shift FPM. The presented here uses silicon strip waveguides integrated MEMS on single...

We propose a tunable erbium doped fiber laser based on Fabry-Pérot (F-P) cavity tuned by an electrostatic actuator. The device is made of single crystalline silicon. F-P consists two Bragg mirrors, one being displaced comb-drives cavity, grooves for optical fibers and electro-mechanical structure are fabricated deep reactive ion etching 70 μm silicon insulator wafer integrated in ring laser. resulting has tuning range 35 nm the C-band spectral width less than 0.06 nm. maximum applied voltage...

Typical adaptive optics (AO) applications require continual measurement and correction of aberrated light form closed-loop control systems. One the key components in microelectromechanical system (MEMS) based AO systems is parallel-plate microactuator. Being electrostatically actuated, this type devices inherently instable beyond pull-in position when they are controlled by a constant voltage. Therefore extending stable travelling range such forms one central topics MEMS. In addition, though...

We report the first observation of a nonlinear process in chalcogenide microresonator. Raman scattering and stimulated leading to laser oscillation is observed microspheres made As2S3. The coupled pump power threshold as low 13 μW using wavelength 1550 nm. quality factor microresonator also highest ever reported with Q>7×107.

Optical resonant microcavities with ultra high quality factors are widely used for biosensing. Until now, the primary method of detection has been based upon tracking wavelength shift as a function biodetection events. One sources noise in all resonant-wavelength measurements is due to intensity fluctuations laser source. An alternative approach track change factor optical cavity by using phase ring down spectroscopy, technique which insensitive Here, biotinylated microtoroid cavities, we...

Whispering Gallery Mode (WGM) microresonators have recently been studied as a means to achieve real-time label-free detection of biological targets such virus particles, specific DNA sequences, or proteins. Due their high quality (Q) factors, WGM resonators can be highly sensitive. A biosensor also needs selective, requiring proper functionalization its surface with the appropriate ligand that will attach biomolecule interest. In this paper, microdisks are used biosensors for Staphylococcus...

Sensitivity of polymeric microdisks is evaluated for selected compounds in their vapor phase such as humidity, isopropanol, toluene, limonene, 1-butanol, and pentanoic acid (valeric acid). Among these compounds, exhibits the highest sensitivity (23 pm/ppm) with a limit detection estimated to be around 0.6 ppm. We are interested contribution geometry deformation due polymer swelling on it may engineered improve performance gas sensing devices. Experimental observations show trend where...

A novel in-plane Silicon-On-insulator (SOI) optical accelerometer using a Fabry-Perot microcavity with two distributed Bragg reflectors (DBR) is presented, in which one DBR mirror attached to suspended proof masses. As consequence of acceleration, the relative displacement movable respect fixed changes cavity length and modifies resonance. All device components are fabricated by single fabrication step. The sensor performance could reach ¿g resolution demonstrated 2.5 nm/g sensitivity 400 resolution.

We present recent advances in modeling, design, and fabrication of in-plane multilayer optical resonators fabricated by high aspect ratio etching silicon. first revisit the model Gaussian beam divergence proposed A. Lipson to correct a mistake that leads an underestimation losses affecting this type resonator. Secondly, we discuss influence surface roughness at silicon-air interfaces multilayered structures. Roughness profiles-measured white light interferometry on sidewalls silicon trenches...

We report the observation of cascaded Raman lasing in high-Q As₂S₃microspheres. Cascaded stimulated scattering emission is obtained up to 5th order for a pump wavelength 1557 nm and 3rd 1880 nm. High-Q As₂S₃microspheres are used self-frequency locking laser setup without an external source. Threshold curves measurements presented follow expected coupled mode theory behavior with sub-mW threshold power.

Rapid, specific detection of pathogenic bacteria remains a major challenge in infectious disease diagnostics. Bacteriophages can show genus- or even species-level specificity and have been developed for biosensing purposes, but the possibility using individual phage proteins has not fully explored. This work exploits ability proteins, endolysins LysK Φ11, bacteriocin lysostaphin, fixed on silicon wafers to bind staphylococci. The activity against eight tested clinical isolates S. aureus...

Thulium-doped (Tm-doped) tellurite glass microspheres are used as laser media. Emission lines at wavelengths near 1975 nm observed. The onset of emission is achieved with 8.6 and 30 μW coupled pump power injected power, respectively, a wavelength 1554 nm. To the authors' knowledge, these lowest threshold values recorded for Tm-doped microcavity. Intrinsic Q-factors above 10(6) undoped assert quality fabrication processes. An optical intrinsic Q-factor comparison between shows that ion...

We report a whispering gallery mode resonator on pillar using inkjet printing combined with traditional microfabrication techniques. This approach enables several different polymers the same chip for sensing applications. However, inherently exhibit sensitivity to multiple stimuli. To mitigate temperature sensitivity, careful selection of design parameters is crucial. By precisely tuning undercut-to-radius ratio resonator, linear dependence in ranging from −41.5 pm/°C 23.4 pm/°C,...

We characterize the transmission spectra of out-of-plane, normal-incidence light two-dimensional silicon photonic crystal slabs and observe excellent agreement between measured data finite-difference time-domain simulations over 1050-1600-nm wavelength range. Crystals that are 340 nm thick have holes 330-nm radius on a square lattice 998-nm pitch show 20-dB extinction in from 1220 to 1255 nm. Increasing hole 450 broadens band further, we obtain >85% 1310 1550 Discrepancies simulation...

This paper presents a new sidewall smoothing process for Si micro-optical components using focused ion beam (FIB) milling. First, the deep reactive etching (DRIE) Bosch is employed to form microstructure on substrate. However, scalloping which induced by repetition of and passivation steps major source light scattering, reducing surface reflectivity in optical applications. In this research, FIB used smooth rough obtain polished mirror surface. After DRIE process, values roughness as...

Using finite-difference time-domain method, we investigate photonic crystal slabs consisting of spherical voids or silica beads embedded into a dielectric slab as bio-chemical sensors. We study the dependence spectral position guided-mode resonances on refractive index material. The most sensitive design is based filled with analyte. also effects and analyte thicknesses resonance properties. eventually demonstrate an aqueous sensor high sensitivity at visible wavelength electro-magnetic...

Photonic crystal reflector (PCR) membranes exhibit a resonantly enhanced normal-incidence reflectivity. Many applications require this resonance to occur at specific wavelength, however, imposing geometrical tolerances that are not reliably achieved with standard nanolithography. Here we finely tune the resonant wavelength of freestanding Si3N4 PCR membrane iterative hydrofluoric acid etches, achieving 57 nm thin 0.15 (0.04 linewidths) away from our target (1550 nm). This exhibits broader,...

Abstract Dendritic cells (DCs) patrol the organism at an immature stage to detect presence of pathogens. Once activated, these mature DCs reach lymph nodes activate antigen-specific T lymphocytes and thus initiate adaptative immune response control pathogen. The migration both is a key process for their optimal function. DC requires transit through narrow constrictions that allowed by high local global deformation capabilities. In addition cytoplasmic changes, nucleus mechanical properties...

Administrative support is concerned with the provision of secretarial and administrative services to students, faculty, other customers educational institutions. In effect, any assistance provided by staff students faculty that benefits institution's overall well-being constitutes an service. Despite their complementary role in teaching learning process, it appears from literature receive little attention when comes students’ evaluation university for quality assurance. This article reviews...