We have fabricated compact optical modulators consisting of a Si waveguide with VO2 cladding layer. These devices showed sharp decrease in transmittance at around 60 °C, which is attributable to the metal-insulator transition By systematically varying length device, we evaluated transmission losses per unit device be 1.27 dB/µm, when layer was insulating (ON) state and 4.55 dB/µm it metallic (OFF) state. Furthermore, found that an additional loss OFF state, structural effect. As result,...

In the past few years, aprotinin has been used in cardiac surgery with impressive results of reducing blood loss, but several adverse effects also have reported. One most likely mechanisms is inhibition plasmin by aprotinin, although this indirect effect not reproduced all experimental studies.We evaluated platelet function and fibrinolytic activity during human surgery, or without aprotinin. During cardiopulmonary bypass (CPB) humans (n=16), decrease aggregation induced thrombin, increase...

Low-loss amorphous-silicon (a-Si) waveguides comprising three vertically stacked layers prepared on silicon-on-insulator substrates are demonstrated. We have fabricated multilayer a-Si and investigated their loss characteristics; this is the first such investigation to our knowledge. All process temperatures were regulated below 400 °C for complementary metal oxide semiconductor (CMOS) backend compatibility. When surface roughness sidewall decreased, propagation decreased 3.7 dB/cm even in...

We fabricated a novel lateral-current-injection-type distributed feedback (DFB) laser with amorphous-Si (a-Si) surface grating as step to realize membrane lasers. This consists of thin GaInAsP core layer grown on semi-insulating InP substrate and 30-nm-thick a-Si for DFB grating. Under room-temperature continuous-wave condition, low threshold current 7.0 mA high efficiency 43% from the front facet were obtained 2.0-μm stripe width 300-μm cavity length. A small-signal modulation bandwidth 4.8...

Silicon photonics enabling ultra-small photonic integrated circuits induces a necessity to develop efficient optical couplers that connect silicon waveguides with fibers or offchip other components. Vertical are promising for both wafer-level testing and the integration of components on chip surface, but so far grating have been only solution virtually. Very recently, we developed few-micron-scale vertically-curved waveguide coupler "elephant coupler" formed by ion implantation method. This...

Low-power and compact optical interconnects can be realized using III–V membrane photonic integrated circuits fabricated from thin InP-based films bonded to a Si wafer benzocyclobutene (BCB) adhesive bonding method. However, the conditions of fabrication process strongly affect propagation loss waveguides. This study investigated during waveguide with view reducing loss. It was found that clean, large GaInAsP without air voids or fractures could obtained by an appropriate solvent...

Flexible and localized initial alignment control of liquid crystal (LC) is important to enhance the performance functionality LC hybrid silicon photonic devices. This work proposes an technique based on integration a nanometer-scale groove array in buried oxide layer near Si waveguide. We achieved angle director around waveguide by selecting required integrated direction reduced driving voltage introducing vertical into phase shifter. then used local flexible controllability develop...

As a step toward the realization of injection-type membrane distributed feedback (DFB) lasers, which are expected to be important components optical interconnections, we realized lateral-current-injection DFB (LCI-DFB) lasers with surface grating structures prepared on semiinsulating InP substrates. First, designed structure have high index-coupling coefficient together confinement in quantum wells. Then, investigated formed an amorphous-Si (a-Si) layer deposited GaInAsP/InP initial wafer...

The integration of III–V active devices on a Si platform utilizing direct bonding is an attractive way to realize large-scale photonic integrated circuits. Because plasma activated (PAB) expected have higher strength at lower heating temperature as compared conventional methods, PAB for the reduction non-radiative recombination centers in region caused by thermal expansion during process. A GaInAsP/Si hybrid laser was fabricated with low-temperature (150 °C) N 2 PAB, and low threshold...

Low-loss amorphous-silicon (a-Si) waveguides comprising three vertically stacked layers prepared on silicon-on-insulator substrates are demonstrated. We have fabricated multilayer a-Si and investigated their loss characteristics; this is the first such investigation to our knowledge. All process temperatures were regulated below 400 °C for complementary metal oxide semiconductor (CMOS) backend compatibility. When surface roughness sidewall decreased, propagation decreased 3.7 dB/cm even in...

Inter-layer grating couplers sandwiched by two metal layers were demonstrated for high coupling efficiency vertical between amorphous-Si:H multi-stacked optical waveguides. A of 83% was achieved with formed on 5 μm wide waveguides separated 1 while theoretical 90% obtained.

An athermal Si-slot-waveguide ring resonator embedded with benzocyclobutene (BCB), a low- k material used in electronics, was proposed. By controlling the width of BCB-filled gap to 90 nm, temperature coefficient equivalent index Si slot waveguide could be reduced 3.70×10 -6 , which is two orders magnitude smaller than that conventional waveguide. The dependences peak wavelength shift on fabricated devices wire SiO 2 cladding, BCB and cladding were 26, 17, -0.6 pm/K, respectively.

A surface optical coupler based on a vertically curved Si waveguide was designed for coupling with high-numerical aperture single-mode fibers mode-field diameter of 5 µm. This has quite small device size, height approximately 12 µm, achieved by introducing an effective spot-size converter configured the combination extremely short exponential-inverse taper and dome-structured SiO2 lens formed top. The shows high-efficiency coupling, loss 0.8 dB TE polarized light, as well broad-band...

The fabrication of highly efficient interlayer grating couplers for multilayered a-Si:H waveguides by introducing two metal mirrors to reflect back the diffracted light was demonstrated. coupling efficiency from one layer next 83% (loss 0.8 dB). 50 Gbps signals were successfully transmitted without any eye degradation.

We investigated the switching dynamics of optical modulators consisting a Si waveguide with VO 2 cladding layer by utilizing photothermal effect, which induces metal–insulator transition in . The devices exhibited stable high extinction ratio exceeding 16 dB. time insulator-to-metal (heating process) ranged from tens nanoseconds to microseconds depending on incident light power, and that metal-to-insulator (cooling was several regardless power. heat transfer numerically simulated reproduce...

A high-index-contrast grating coupler based on hydrogenated amorphous silicon (a-Si:H) was demonstrated as a layer-to-layer coupler. a-Si:H deposited by plasma-enhanced chemical vapor deposition and vertically stacked with SiO 2 for multilayer integration. The distance between the waveguides fixed to 1 µm optical isolation. pair fabricated basis of simulation results. From measurements in C-band, maximum coupling efficiency estimated be 22%.

For silicon wire based ring resonator biosensors, we investigate the simultaneous retrieval of changes in fluidic refractive index ∆n(c) and surface adsorbed molecular film thickness ∆d(F). This can be achieved by monitoring resonance shifts sensors operating TE TM polarizations at same time. Although this procedure is straightforward principle, significant errors introduced due to deviations sensor waveguide cross-sections from their nominal values range commonly encountered for photonic...

Flexible endoscopes can be used in areas that are difficult to approach using rigid endoscopes. No current real-time navigation systems identify the tip of flexible neuroendoscope. We have developed a neuroendoscope mounted with magnetic field sensor position-tracking system and evaluated accuracy this neuronavigation system. Based on an existing neuroendoscope, we created prototype built-in tip. A measurement device provides working volume 500 × mm front device. The consists flat generator...

The relationship between the propagation loss and roughness on multi-layered Si waveguides fabricated up to a 3^rd layer was investigated. By reducing surface sidewall of waveguides, low 3.7 dB/cm for 3 a-Si:H demonstrated. Furthermore, vertical coupling multilayer demonstrated by use grating-type coupler. A efficiency 22% obtained 10 pairs gratings with period 640 nm, even distance 1μm.

Photonic integrated circuits (PICs) produced by large-scale integration (LSI) on Si platforms have been intensively researched. Since thermal diffusion from the LSI logic layer is a serious obstacle to realizing Si-based optical circuit, we proposed and realized athermal wavelength filters using slot waveguides embedded with benzocyclobutene (BCB). First, conditions were theoretically investigated controlling waveguide gap width of waveguides. In order introduce calculated structures...