On-Chip All-Optical Passive 3.55 Gbit/s NRZ-to-PRZ Format Conversion Using a High-Q Silicon-Based Microring Resonator

We report the experimental result of all-optical passive 3.55 Gbit/s non-return-to-zero (NRZ) to pseudo-return-to-zero (PRZ) format conversion using a high-quality-factor (Q-factor) silicon-based microring resonator notch filter on chip. The silicon-based microring resonator has 23800 Q-factor and 22 dB extinction ratio (ER), and the PRZ signals has about 108 ps width and 4.98 dB ER.

A Novel Power Supply Solution of a Passive RFID Transponder

This paper presents a power supply solution for fully integrated passive radio-frequency identification(RFID) transponder IC,which has been implemented in 0.35μm CMOS technology with embedded EEPROM from Chartered Semiconductor.The proposed AC/DC and DC/DC charge pumps can generate stable output for RFID applications with quite low power dissipation and extremely high pumping efficiency.An analytical model of the voltage multiplier,comparison with other charge pumps,simulation results,and chip testing results are presented.

Contrastive study of two SESAMs for passive mode-locking in Nd:YVC>4 laser with low pump power

Two semiconductor saturable absorber mirrors (SESAMs), of which one is coated with 50% reflection film on the top and the other is not, were contrastively studied in passively mode-locked solid-state lasers which were pumped by low output power laser diode (LD). Experiments have shown that reducing the modulation depth of SESAM by coating partial reflection film, whose reflectivity is higher than that between SESAM and air interface, is an effective method to get continuous wave (CW) mode-locking instead of Q-switched mode-locking (QML) in low power pumped solid-state lasers. A simple Nd:YVO4 laser pumped by low power LD, in which no water-cooling system was used, could obtain CW mode-locking by the 50% reflector coated SESAM with average output power of ~ 20 mW

Passive Q-switching of diode-pumped Yb:YAG microchip laser with ion-implanted GaAs

We reported a passive Q-switched diode laser pumped Yb:YAG microchip laser with an ion-implanted semi-insulating GaAs wafer. The wafer was implanted with 400-keV As^(+) in the concentration of 10^(16) ions/cm^(2). To decrease the non-saturable loss, we annealed the ion-implanted GaAs at 500 oC for 5 minutes and coated both sides of the ion-implanted GaAs with antireflection (AR) and highreflection (HR) films, respectively. Using GaAs wafer as an absorber and an output coupler, we obtained 52-ns pulse duration of single pulse.

Passive mode locking of an Yb:YAB laser with a low modulation depth SESAM

A passive mode-locked diode-pumped self-frequency-doubling Yb:YAB laser with a low modulation depth semiconductor saturable absorber mirror operating at 374 MHz is demonstrated. The measured pulse duration is 1.98 ps at the wavelength of 1044 nm. The maximum average power reaches 45 mW.

Passive Q-Switching in a Flash-Lamp Pumped Nd∶YAG Laser with Ion-Implanted GaAs Wafer

A passive Q-switched flash-lamp-pumped Nd:YAG laser with the ion-implanted semi-insulating GaAs water is reported．The wafer is implanted with 400keV As~+ ions in the concentration of 10~(16)cm~(-2). Using GaAs wafer as an absorber and an output coupler．62ns pulse duration of single pulse is obtained.

Novel High Power Quantum WellLasers With Integrated Passive Waveguide

国家自然科学基金

880 nm LD pumped passive mode-locked TEM00 Nd:YVO4 laser based on SESAM

We report on an 880 nm LD pumped passive mode-locked TEM00 Nd:YVO4 laser based on a semiconductor saturable absorber mirror (SESAM) for the first time. When the incident pump power was 16 W, 4.76 W average output power of continuous-wave mode-locked laser with an optical-to-optical conversion efficiency of 30% was achieved. The repetition rate of mode-locked pulse was 80 MHz with 25 ps pulse width. The maximum pulse energy and peak power were 60 nJ and 2.4 kW, respectively.

LD Side-Pumped Passive Mode-Locked TEM00 Nd:YAG Laser Based on SESAM

We report an LD side-pumped continuous-wave passive mode-locked Nd:YAG laser with a Z-type folded cavity based on a semiconductor saturable absorber mirror (SESAM). The average output power 2.95 W of mode-locked laser with electro-optical conversion efficiency of 1.3% and high beam quality (M-x(2) = 1.25 and M-y(2) = 1.22) is achieved. The repetition rate of mode-locked pulse of 88 MHz with pulse energy of 34 nJ is obtained.

有限积分理论(FIT)及其在腔体计算中的应用

通过介绍麦克斯韦方程的离散过程 ,简单介绍了有限积分理论 ( Finite Integration Theo-ry)。该理论直接以电场强度和磁感应强度为未知量 ,采用两套互相正交的网格 ,将场矢量离散为不同网格点上的一系列分量 ,将矢量积分方程转化为一组线性方程组。通过对 SFC高频腔体模拟的实例 ,可以看出 ,此方法在腔体本征频率、Q值及腔体并联阻抗等腔体参数计算中具有叫高的精度 ,说明了基于FIT的 MAFIA程序在腔体模拟中的可靠性

Undercut structure fabricated by complementary-structure micropatterning technique for the passive-matrix display of organic light-emitting diodes

This paper reports a new patterning method, the complementary-structure micropatterning (CSMP) technique, to fabricate the undercut structures for the passive-matrix display of organic light-emitting diodes (OLEDs). First, the polyvinylpyrrolidone (PVP) stripe patterns with a trapeziform cross-section were formed by micromolding in capillaries. Then the photoresist was spin coated on the substrate with the patterned PVP stripes and developed in water.

Facile synthesis of PtRu/C electrocatalyst with high activity and high loading for passive direct methanol fuel cell by synergetic effect of ultrasonic radiation and mechanical stirring

The PtRu/C electrocatalyst with high loading (PtRu of 60 wt%) was prepared by synergetic effect of ultrasonic radiation and mechanical stirring. Physicochemical characterizations show that the size of PtRu particles of as-prepared PtRu/C catalyst is only several nanometers (2-4 nm), and the PtRu nanoparticles were homogeneously dispersed on carbon surface. Electrochemistry and single passive direct methanol fuel cell (DMFC) tests indicate that the as-prepared PtRu/C electrocatalyst possessed larger electrochemical active surface (EAS) area and enhanced electrocatalytic activity for methanol oxidation reaction (MOR). The enhancement could be attributed to the synergetic effect of ultrasound radiation and mechanical stirring, which can avoid excess concentration of partial solution and provide a uniform environment for the nucleation and growth of metal particles simultaneously hindering the agglomeration of PtRu particles on carbon surface.

Effects on the surface passive film of carbon anode on cell behavior

The properties of the films formed in the electrolyte of PC/DME LiClO4 on two kinds of carbon materials were examined by cathodic polarization measurements. The result suggested that the films on both carbon electrodes have different morphology which resulted in the different cen performance of the two carbon anodes.