16-Channel 0.35μm CMOS/VCSEL Transmission Modules

The vertical cavity surface emitting laser (VCSEL) arrays and VCSEL-based optical transmission modules are investigated.It includes the VCSEL's spectral characteristic,modulation characteristic,high frequency characteristic,and compatibility with microelectronic circuit.The module consists of 1×16 VCSEL array and 16-channel lasers driver with 0.35μm CMOS circuit by hybrid integration.During the test process,the module operates well at more than 2GHz in -3dB frequency bandwidth.

Optimization for Top DBR’s Reflectivity in RCE Photodectector

The monolithic integration of vertical-cavity surface-emitting lasers (VCSEL) with photodetectors is very important in the application of free-space optical interconnects.Theoretical and experimental results on the resonant-cavity-enhanced (RCE) photodetector with VCSEL Structure are presented.The compatible requirement in input mirror reflectivity between the VCSEL and the RCE detector is achieved by precisely etching the top mirror.In this way,the RCE detector with relatively high quantum efficiency and necessary optical bandwidth has been obtained.[KH8/9D]

Design and Characteristics of InGaAs/GaAs MQW SEED Arrays Structure

The influence of DBR in resonant cavity on the characteristics of the reflectivity of InGaAs/GaAs MQW SEED arrays has been discussed. InGaAs/GaAs acting as the active region of MQW SEED to gain 980nm work wavelergth has been introduced. A new resonant cavity structure of the InGaAs/GaAs MQW SEED arrays has been designed and analyzed. The MQW materials grown by MOCVD system have also been measured and analyzed with micro optical spot reflection spectra, PL measurement and X ray measurement. The results of measurement prove the good quality of the wafer and the accuracy of our design and analysis of the structure of the device.

Special requirements for alumina ceramic of ESG electrode bowl

At present ESG (Electrostatic Suspended Gyro) is the most precise inertia element in the world. The electrode bowl, which has direct effect on the precision of ESG, is a key part to ESG. Through the analysis of the function and characteristic of the electrode bowl in hollow rotor ESG and the present situation of new material development in the world, the alumina ceramic is regarded as the best material for the electrode bowl of hollow rotor ESG. By analyzing the present situation of alumina ceramic in the world, main technique requirements have been put forward for the alumina ceramic of ESG electrode bowl which is also fit for solid rotor ESG.

Implementation of a Controlled-Phase Gate and Deutsch-Jozsa Algorithm with Superconducting Charge Qubits in a Cavity

Based on superconducting quantum interference devices （SQUIDs） coupled to a cavity, we propose a scheme for implementing a quantum controlled-phase gate （QPG） and Deutsch-Jozsa （D J） algorithm by a controllable interaction. In the present scheme, the SQUID works in the charge regime, and the cavity field is ultilized as quantum data-bus, which is sequentially coupled to only one qubit at a time. The interaction between the selected qubit and the data bus, such as resonant and dispersive interaction, can be realized by turning the gate capacitance of each SQUID. Especially, the bus is not excited and thus the cavity decay is suppressed during the implementation of DJ algorithm. For the QPG operation, the mode of the bus is unchanged in the end of the operation, although its mode is really excited during the operations. Finally, for typical experiment data, we analyze simply the experimental feasibility of the proposed scheme. Based on the simple operation, our scheme may be realized in this solid-state system, and our idea may be realized in other systems.

Theoretical and Practical Study on RF Model Cavity of 100MeV H^- Cyclotron

In a cyclotron,the RF cavity is the key device to accelerate ions.The RF cavity design for the 100MeV H^- cyclotron is very complex since the space is narrow and the Dee voltage is 60kV at the center and 120kV at the extraction region.CST MICROWAVE STUDIO is used in the design,and a real model has been made.The test result on the model is in good agreement with the simulation result.

A coupled optoelectronic oscillator with three resonant cavities

A new single-mode optoelectronic oscillator(OEO) with three coupled cavities is proposed and demonstrated. A Fabry-Perot(F-P) cavity fiber laser and an optical-electrical feedback branch are coupled together to construct an optoelectronic oscillator, where the F-P cavity fiber laser serves as a light source, and a modulator is placed in the laser cavity to implement reciprocating modulation, which simultaneously splits the laser cavity into two parts and forms a dual-loop configuration. To complete an optoelectronic oscillator, part of optical signal is output from the F-P cavity to implement the feedback modulation, which constructs the third cavity. Since only the oscillation signal satisfies the requirements of all the three cavities, a single-mode oscillation can be finally achieved. Three resonant cavities are successfully designed without adding more optoelectronic devices, and the side-modes can be well suppressed with low cost. The oscillation condition is theoretically analyzed. In the experimental demonstration, a 20 GHz single longitudinal mode microwave signal is successfully obtained.