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41.
Chlorine auto-doping phenomenon was found for the first time in InP epitaxial growth by using a PCl3/InP/H2 system. Chlorine atoms act as a donor in the epitaxial layer and the carrier concentration is dependent on the facet of InP
substrate. The carrier concentration of the InP layer on ( 111)B facet was over 103 times higher than that on (111)A substrate. 相似文献
42.
S Iwata N Sakuma T Hibino T Sato A Yoneyama Y Kamiya M Kawaguchi T Fujinami M Kunimatsu 《Canadian Metallurgical Quarterly》1995,28(3):309-311
Results 2 1/2 years after an enuresis nocturna training are presented, including rate of success, percentage and duration of relapse for 113 children (mean age 11.6 year at the start of the training). The bibliotherapeutic treatment by parents did not require any intervention by a professional. Behaviour of parents in the event of a relapse differed between training conditions. Children in the Arousal condition recovered faster from a relapse, 90% of their parents used the Arousal training again at relapse or did not intervene at all and none of them consulted a professional. Clearly they had confidence in the method of Arousal training: combining the alarm device with reinforcement for correct behaviour at the time the alarm goes off. Parents in control conditions did not use the alarm device as often as the parents in the Arousal condition, but tried other means with less success, including consulting professionals. 相似文献
43.
Yoneyama M. Shibata T. Sano E. Kawamura Y. Takahashi R. Enoki T. Nagatsuma T. Yaita M. 《Quantum Electronics, IEEE Journal of》1997,33(8):1308-1315
A novel photoconductive AND gate that overcomes the problems of: 1) the long tail of photoconductive switches and 2) signal leakage via switch capacitance (signal feedthrough) is proposed. We use Be-doped low-temperature (LT)-grown InGaAs-InAlAs MQW metal-semiconductor-metal photodetectors (MSM-PD's) to get a shorter turn-off time and propose a differential AND gate to cancel the signal feedthrough. A comparison between LT-grown MSM-PD's and those fabricated by ion implantation shows that the LT-grown ones are ultrafast with a full width at half maximum of 5.3 ps and are suitable for low-bias operation. It is experimentally confirmed that the differential AND gate completely cancels the signal feedthrough in the picosecond region. The differential AND gate: with the LT MSM-PD's achieves return-to-zero (RZ) 20 Gb/s AND operation 相似文献
44.
H. Takeuchi K. Tsuzuki K. Sato M. Yamamoto Y. Itaya A. Sano M. Yoneyama T. Otsuji 《Photonics Technology Letters, IEEE》1997,9(5):572-574
NRZ operation at 40 Gb/s has been successfully performed using a very compact module of a multiple-quantum-well (MQW) electroabsorption modulator integrated with a distributed-feedback (DFB) laser. While the DFB laser is injected with a constant current, the integrated MQW electroabsorption modulator is driven with a 10-Gb/s electrical NRZ signal. A clearly opened eye diagram has been observed in the modulated light from the modulator. And a receiver sensitivity of -27.2 dBm at 10/sup -9/ has been experimentally confirmed in the bit-error-rate (BER) performance. 相似文献
45.
Guided modes in a vertical strip line embedded in a non-radiative dielectric (NRD) guide were analysed based on the two-dimensional finite-element method. The dominant mode in this guiding structure is the TEM wave, and furthermore, it is evident that a quasi-LSM/sub 11/ odd mode occurs when a wide metal strip is used, whereas a quasi-LSE/sub 01/ even mode is generated when a narrow strip is employed. 相似文献
46.
This paper proposes a novel model for estimating power dissipation of optical/electrical interconnections as a function of transmission bit error rate. This model is applied to a simplified optoelectronic transmitter and receiver configuration in which a photodetector is directly connected to the decision circuit. It is analytically verified that this configuration can achieve error-free operation with low power under practical operating conditions. A comparison between optical and electrical interconnections based on this simplified configuration is performed. This result shows the interconnection length and bit rate at which optical interconnection is superior in terms of power dissipation to electrical interconnection, Only optical interconnections achieve error-free operation with 40 mW power dissipation at a transmission bit rate of 10 Gb/s and an interconnection length over 7 m 相似文献
47.
T Kitagawa M Kakehi T Kunieda I Tsukiyama M Hamada H Inakoshi M Sakudo K Suemasu K Matsumoto T Yoneyama T Iizuka K Nomura K Kawachi 《Canadian Metallurgical Quarterly》1982,143(2):543-547
An afterloading procedure using iridium 192 seeds was developed for the control of both localized primary lesions that are difficult to remove and superficial residual lesions that remain after the partial removal of tumors in relatively inaccessible, deep-seated organs. This technique makes possible the delivery of a minimal radiation dose to lesions in deep-seated organs. Fewer complications result, the seeds can be adjusted at appropriate intervals in proportion to the amount of radioactivity desired, and radiation exposure to personnel can be reduced. This paper describes the techniques and apparatus used to place the seeds in the tubing. Primary lesions of the urinary bladder, the prostate gland, and the esophagus, residual lesions in the brain and lung, and metastases in intrapelvic lymph nodes were treated. No technical difficulties or complications were encountered. Radiation exposures to personnel were minimized. The results indicate that the procedure has practical applications. 相似文献
48.
A new type of dielectric waveguide, which we call a tube-contacted slab waveguide, is proposed for millimetre and sub-millimetre waves. Transverse sizes of the waveguide can be made much larger than the wavelength. Dispersion characteristics and field distributions of the guided modes are calculated using the method of effective dielectric constant. 相似文献
49.
A simple method is presented for obtaining approximate expressions for the power reflection and transmission coefficients of surface waves scattered by a step discontinuity in a dielectric slab waveguide. The approximation is compared with Rozzi's exact solution. Agreement is quite good for a wide range of the relevant parameters. 相似文献
50.
A new type of H-guide is proposed which is more than ten times as large as the conventional H-guide in transverse dimensions, but can operate in a single mode. A single order of magnitude reduction in attenuation over the single-strip and double-strip H-guide can be achieved with this oversize H-guide 相似文献