不同状态MnO2对废水中As（III）的吸附研究

于2010-11-23批量导入

980 nm InGaAs应变量子阱激光器和掺铒光纤放大器用泵浦源

利用分子束外延技术研制出了高质量InGaAs/GaAs应变量子阱材料及量子阱激光器。在室温和10 K温度下,应变量子阱材料的光荧光峰值半宽分别为32 meV和.4 meV,宽接触激光器的阈值电流密度低达140 A/cm~2。脊形波导窄条形量子阱激光器的阈值电流和微分量子效率分别为15 mA和0.8 W/A,线性输出功率大于120 mW,基横模输出功率可达100 mW。InGaAs应变量子阱激光器和单模光纤进行了耦合其组合件出纤光功率典型值为40 mW,最大值可达60 mW,显示出了高的基横模输出功率和高的耦合效率。其组合件在40 mW下,中心发射波长在977 nm,成功地研制出适于掺铒光纤放大器用的应变量子阱激光器泵浦源。

MOCVD growth of high quality crack-free GaN on Si(III) substrates

High quality crack free GaN epilayers were grown on Si(111) substrates. Low temperature AlN interlayer grown under low V/III ratio was used to effectively eliminate the formation of micro-cracks. It is found that tensile stress in the GaN epilayer decreases as the N/Al ratio decreases used for AlN interlayer growth. The high optical and structural qualities of the GaN/Si samples were characterized by RBS, PL and XRD measurements. The RT-PL FWHM of the band edge emission is only 39.5meV The XRD FWHM of the GaN/Si sample is 8.2arcmin, which is among the best values ever reported.

High power 980 nm Al-free strained quantum-well lasers for erbium-doped fiber amplifiers

In this paper, we reported on the fabrication of 980 nm InGaAs/InGaAsP strained quantum-well (QW) lasers with broad waveguide. The laser structure was grown by low-pressure metalorganic chemical vapor deposition on a n(+)- GaAs substrate. For 3 mu m stripe ridge waveguide lasers, the threshold current is 30 mA and the maximum output power and the output power operating in fundamental mode are 350 mW and 200 mW, respectively. The output power from the single mode fiber is up to 100 mW, the coupling efficiency is 50%. We also fabricated 100 mu m broad stripe coated lasers with cavity length of 800 mu m, a threshold current density of 170 A/cm(2), a high slope efficiency of 1.03 W/A and a far-field pattern of 40 x 6 degrees are obtained. The maximum output power of 3.5 W is also obtained for 100 mu m wide coated lasers. (C) 2000 Elsevier Science B.V. All rights reserved.

Characterization of GaSb substrate wafers for MOCVD III-V antimonides

The qualities of GaSb substrates commonly used for the preparation of III-V antimonide epilayers were studied before and after growing GaInAsSb multi-layers by MOCVD using PL, FTIR and DCXD together with the electrical properties and EPD value. The correlation between the substrate qualities and epilayer properties was briefly discussed. The good property epilayers of GaInAsSb and, then, the high preformance of 2.3 um photodetectors were achieved only using the good quality GaSb wafers as the substrates.