A p-n junction is formed for the first time in a cross-sectional area of GaAs wire crystal with diameter about 100 nm. Ultrafine cylindrical growth by metalorganic vapor phase epitaxy employed fabrication. Current-voltage and capacitance-voltage characteristics confirm formation narrow at midpoint crystal. Intensive light emission current injection observed 77 K even room temperature. These results suggest that ultrafine optoelectronic devices quantum-size are possible.

Ultrathin GaAs wires as thin 15–40 nm and about 2 μm long have been grown on a substrate by metal-organic vapor-phase epitaxy. The wires, which consist of whiskers, are between 380 550 °C using trimethylgallium arsine (AsH3) source materials. It is found that the wire growth direction parallel to [111] arsenic dangling-bond can be perfectly controlled crystallographic orientation surface. From transmission electron microscopic analysis it revealed crystal structure coincides with zinc-blende...

Silicon Mach-Zehnder modulators with reduced series resistance in lateral PN junction rib-waveguide phase shifters for enhanced high-speed response are fabricated and characterized. Extinction ratio higher than 10 dB is obtained at 10.3-11.7 Gbps mask margins of 27% (10.3-Gbps 10GBE), 16% (10.7-Gbps STM-64/OC-192) 10% (11.3-Gbps eye-diagram measurements incorporating tests using a RF cut-off filter. In unfiltered without tests, extinction 13 10.0-12.5 Gbps. The silicon reveal performance...

The authors reveal a key to improving the life of MOCVD-grown AlGaAs/GaAs heterojunction bipolar transistors with carbon-doped base. In addition presenting new findings on current gain degradation properties, it is shown that importance lattice strain relaxation in base layer. Indium was incorporated into C-doped GaAs relax by controlling constant layer, which slightly shrunk carbon doping. Although lifetime testing still underway, median estimated be longer than 2.8 /spl times/ 10/sup 6/...

We present a low-loss and small-footprint polarization rotator based on mode evolution. The is composed of an asymmetric-rib waveguide tapered waveguide, both which consist only silicon core silica cladding. fabricated under the same design rules as other device blocks, such rib-waveguide phase shifters for photonic integration. using CMOS-based processes provides rotations with on-chip insertion loss lower than 0.5 dB from transverse-electric (TE) to transverse-magnetic (TM) 1.0 TM TE in...

Abstract Nanodiamonds (NDs) are quantum sensors that enable local temperature measurements, taking advantage of their small size. Though model-based analysis methods have been used for ND thermometry, accuracy has yet to be thoroughly investigated. Here, we apply model-free machine learning with the Gaussian process regression (GPR) thermometry and compare its capabilities existing methods. We prove GPR provides more robust results than them, even a number data points regardless acquisition...

The 11-Gbps 80-km transmission performance of a zero-chirp silicon Mach-Zehnder modulator has been characterized. characteristic the is confirmed in constellation measurement, and gives high tolerance both for positive negative chromatic dispersion. A low-dispersion-penalty up to 80 km using non return-to-zero on-off-keying format via bit-error-rate measurements with comparable that commercial lithium-niobate modulator. dispersion at 2-dB power penalty 10(-3) more than ± 950 ps/nm. Further,...

44.6-Gb/s DQPSK and 50-to-64 Gb/s QPSK modulation are demonstrated using low-loss nested Silicon MZ modulator with fiber-to-fiber loss of 10dB. Dispersion tolerance +/−80 ps/nm is observed in the transmission.

We have simulated the phase noise of a voltage controlled oscillator (VCO) using an RF circuit simulator, SpectreRF/sup TM/. This simulator uses variation periodic analysis first proposed by Okumura, et al (1993). It computes power spectral density as function frequency. By assuming that only white sources are present in oscillator, it is possible to derive simple relationship between level and jitter. excludes flicker from consideration, however, since low-frequency phenomenon, excluding...

A low-loss high-speed silicon in-phase (I) quadrature (Q) modulator is designed, fabricated and characterized. The IQ has a low passive optical loss of 9 dB in C L bands. Using the modulator, differential phase-shift keying (DQPSK) transmission at 44.6 Gb/s with detection confirmed an signal-to-noise ratio (OSNR) 16.3 for bit error rate (BER) 10(-3) dispersion tolerance -96 to 107 ps/nm. Moreover, digital coherent detection, (QPSK) up 64 are achieved OSNR 11.6-11.8 BER 10(-2) 1530, 1550, 1610 nm.

Anisotropic propagation of excitonic polaritons in GaAs single-quantum-well waveguide structures is evidenced by means time-of-flight measurements. This anisotropy suggests that the depolarization effect two-dimensional excitons enhances polariton propagation. The observed optical nonlinearity group velocity supports existence and reflects a polariton-polariton interaction on their

We experimentally evaluated the transmission performance of discrete multi-tone (DMT) modulation with 10-Gbps SiP MZ modulator at 1550-nm region. achieved more than 130-Gbps over 2-km SMF BER FEC limit 3.0E-03.

128-Gb/s DP-QPSK is realized using silicon IQ modulator monolithically integrated with partial-rib polarization rotator under +/−3.25-Vpp push-pull RF driving condition. Low passive insertion loss 12–13 dB achieved over C band.

Abstract Quantitative DNA amplification using fluorescence labeling has played an important role in the recent, rapid progress of basic medical and molecular biological research. Here we report a label-free detection real-time nanofluidic diffraction grating. Our system observed intensity changes during diffracted light derived from passage laser beam through nanochannels embedded microchannel. Numerical simulations revealed that change grating was attributed to refractive index. We showed...

Carrier-depletion Si Mach-Zehnder modulators incorporating lateral PN-junction phase shifters are reviewed in the lights of fundamental characteristics and applications to high-speed optical fiber transmission. Experimental reverse-bias supported by numerical analysis with good agreement, implying that fabricated precisely as designed. Numerical response proves shifter operates beyond 100-Gbaud symbol rate. Traveling-wave electrodes characterized S-parameter measurements reveal LRC resonance...

We present technical specifications and experimental results of test running a railway vehicle powered by fuel cells in this paper. are currently under development equipped with cells. made trial product 100-kW class cells, carried out tests. This paper has focused on the following features: (a) Specifications for cells: Fuel hydrogen storage cylinders, motors, inverter (b) Outline vehicle, equipment layout configuration traction circuit (c) Experimental track Motor characteristic train...

We investigate the detection characteristics of a vertical p-n junction embedded waveguide in low-gain region and strong avalanche gain region. Due to "L" shape relatively high doping concentration, photon absorption is enhanced working bias reduced. The has linear response input power wide dynamic range continuous wavelength throughout C+L bands. obtain responsivity 0.54 A/W, 3-dB OE bandwidth 26 GHz gain-bandwidth product 28 THz at -9 V proposed device. Up 28-Gb/s NRZ-OOK signal...

In this paper, we report the efficiency and loss performance of a depletion silicon rib phase shifter with an overlayer 220 nm doping concentration 5 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">17</sup> cm xmlns:xlink="http://www.w3.org/1999/xlink">–3</sup> for both p n regions. A <inline-formula xmlns:xlink="http://www.w3.org/1999/xlink"><tex-math notation="LaTeX">${{\rm{V}}_{\rm pi}}$</tex-math></inline-formula> 3.6 V 5.2 dB, 4-mm...

An excitonic polariton is a complex quasiparticle that consists of photon and an exciton. Excitonic polaritons have recently been shown to exist in quantum-confined systems such as GaAs quantum wells. Based on the coherent coupling between charged electron (hole) light, has characteristics large coherence length phase modulation under electric fields. Furthermore, because inherent refractive index, spatial shape guided mode transmitted waveguides expected be squeezed significantly. We...

Silicon photonic waveguide nested Mach-Zehnder modulators having rib-waveguide planar P-N junction phase shifters are fabricated and characterized in constellation transmittance measurements. 20-Gbps QPSK is observed with optical loss lower than 15 dB at wavelengths of 1550 1590 nm.

Low-loss high-speed traveling-wave silicon Mach-Zehnder modulator with reduced series resistance is studied in microwave and optical measurements. Microwave impedance propagation loss under reverse bias are characterized by S-parameter Resonant due to inductance-resistance-capacitance coupling limits performances of the modulator. High-speed characterized, based on eyediagram measurements on-off keying at 10-32 Gb/s constellation eye-diagram differential phase-shift 20 Gb/s. Dispersion...

We demonstrate 10-Gb/s high-on/off-contrast modulation of a carrier-depletion silicon Mach-Zehnder modulator having 3-mm rib-waveguide phase shifter driven with RF 3.6 VPP or lower at temperatures up to 130 °C without thermo-electric cooling.

An in-plane gate field-effect transistor is characterized by ultrafast electro-optic sampling. The monolithically integrated with photoconductive switches in coplanar waveguide and &amp;lt;0.5 ps measurement time resolution achieved. gate-drain capacitance of the obtained as 1.8 fF at zero drain voltage from displacement current transients. dominated parasitic intrinsic estimated less than 0.2 fF.