Wide-Band Polarization-Insensitive High-Output-Power Semiconductor Optical Amplifier Based on Thin Tensile-Strained Bulk InGaAs

A polarization-insensitive semiconductor optical amplifier (SOA) with a very thin active tensile-strained InGaAs bu/k has been fabricated.The polarization sensitivity of the amplifier gain is less than 1 dB over both the entire range of driving current and the 3dB optical bandwidth of more than 8Onto.For optical signals of 1550nm wavelength,the SOA exhibits a high saturation output power 7.6dBm together with a low noise figure of 7.SdB, fibre-to-fibre gain of 11.5dB,and low polarization sensitivity of 0.5dB.Additionally,at the gain peak 1520nm,the fibre-to-fibre gain is measured to be 14.1 dB.     

Graded tensile-strained bulk InGaAs/InP superluminescent diode with very wide emission spectrum

A kind of novel broad-band superluminescent diodes (SLDs) using graded tensile-strained bulk InGaAs is developed. The graded tensile-strained bulk InGaAs is obtained by changing only group-Ⅲ trimethylgallium source flow during low-pressure metal organic vapor-phase epitaxy. At the injection current of 200mA, the fabricated SLDs with such structure demonstrate full-width at half-maximum spectral width of 106 nm and the output light power of 13.6 mW, respectively.     

Postsynaptic Potentials and Morphological Features of Tectal Cells in Homing Pigeons

In this study postsynaptic potentials responding to the electrical stimulation of the optic nerve and the nucleus isthmipars parvocellularis (Ipc) were intracellularly recorded from 86 tectal cells in pigeons, 13 of which were marked with Lucifer yellow (LY). According to types of postsynaptic potentials and their succesion, the postsynaptic responses could be classified into four types: excitatory postsynaptic potential (EPSP)-inhibitory postsynaptic potential (IPSP) sequence (EI type), E, I and IE types.Among them, E or EI responses were mainly produced to the optic nerve stimulation, while the electrical stimulation of the lpc elicited I responses in more than half the recorded cells.LY-marked tectal cells included five ganglionic cells, four pyramidal cells, two bipolar cells and two stellate cells.The ganglionic cells were mainly located in tectal layers Ⅲ and Ⅳ, whereas the others were in layer Ⅱ.It appears from both intracellular recordings and fluorescent markings that there is some correlati     

硫化温度-时间曲线对铜锌锡硫薄膜性能的影响

采用溅射法制备含硫预制层,硫化时采用不同的升温速率对经过合金处理的含硫预制层进行退火硫化.通过表征薄膜的表面粗糙度,致密性,均匀性来研究硫化时升温速率对薄膜表面形貌的影响.结果表明当升温速率变慢时,薄膜中的CZTS颗粒逐渐增大,虽然较大的颗粒能减少单位面积内的晶界,但是薄膜的表面粗糙度却随颗粒尺寸的增大而逐渐下降.通过对薄膜的元素组分、晶体结构、相成分进行了检测,确定出薄膜的成分为贫铜富锌的单相锌黄锡矿.再通过测量相应的没有Mo层的CZTS薄膜样品的光电特性来间接的反映拥有Mo层的CZTS薄膜的光电特性.最终制备出结构为SLG/Mo/CZTS/CdS/i-ZnO/AZO/Ni/Al-grid的CZTS薄膜太阳电池,其中转换效率最高的电池为3.60;.     

单靶溅射制备铜锌锡硫薄膜及原位退火研究

采用衬底加热溅射铜锌锡硫(CZTS)四元化合物单靶制备CZTS薄膜,并研究原位退火对制备薄膜的影响.结果表明:在溅射结束后快速升温并保持一段时间,所得到的样品相比于未原位退火的CZTS薄膜结晶质量更好,且表面更平整致密;原位退火后的CZTS薄膜太阳电池性能参数也相应地有所提升,其开路电压(V_(OC))为575 mV,短路电流密度(J_(SC))为8.32 mA/cm~2,光电转换效率达到1.82%.     

不同硫化温度对Cu2ZnSnS4薄膜质量及太阳能电池性能的影响

采用ZnS-Sn-CuS作为靶材,利用磁控溅射技术制备了Cu2ZnSnS4 (CZST)薄膜材料及太阳电池,重点研究了不同硫化温度对CZTS薄膜质量及太阳电池性能的影响.利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、能谱仪(EDS)、显微拉曼光谱仪(Raman)和紫外可见分光光度计(UV-Vis)分别表征了不同硫化温度下制备的CZTS薄膜的晶相结构、表面形貌、化学组分、相的纯度和光学性能.结果表明:在580℃下所制备的CZTS薄膜光滑致密、结晶质量好,同时化学组分属于贫铜富锌,而且无其他二次相,禁带宽度约为1.5 eV.符合高效率太阳电池吸收层的要求.将CZTS吸收层按照SLG/Mo/CZTS/CdS/i-ZnO/ITO/ Al的结构制备成面积为0.12 cm2的电池并进行Ⅰ-Ⅴ测试.测试结果表明,在580℃硫化后制备的CZTS薄膜太阳电池具有最高的转换效率为3.59;.     

单质靶溅射制备CZTS薄膜及太阳电池

采用单质靶磁控溅射制备Cu2ZnSnS4 (CZTS)薄膜,研究了薄膜的元素组分、升温速率、硫化温度对薄膜表面平整性以及晶粒尺寸的影响.通过SEM与AFM表征薄膜的表面形貌与表面粗糙度,用EDS检测薄膜的元素组分.所制备的样品的Cu/(Zn+ Sn)、Zn/Sn处于最优范围.通过XRD及Raman检测薄膜的结晶情况以及薄膜中的二次相,经上述测试分析判定CZTS薄膜品质良好.最终制备出以CZTS为吸收层的薄膜太阳电池,并用Ⅰ～V特性检验了CZTS电池性能参数,得到效率为0.83;的CZTS薄膜太阳电池,并通过改进硫化退火工艺将效率提高至1.58;.     

ELECTROPHYSIOLOGICAL STUDIES ON THE NUCLEUS ISTHMI OF THE LIZARDS Gekko gekko AND Shinisaurus crocodilurus

This report studies visual responses of the isthmic units in Gekko gekko and Shinisaurus crocodilurus using extracellular recording and cobalt sulfide marking techniques. Our results indicate that: (ⅰ) the nucleus isthmi pars magnocellularis (Imc) is a visual center; (ⅱ) there are luxotonic units in Imc; (ⅲ) Imc units respond vigorously to moving contrast targets, of which 35% units burst only at the moment when targets are moving into and out of their receptive fields, none react to either tactile or auditory stimulation; (ⅳ) there exist binocular units in Imc; and (ⅴ) visual field is topographically projected onto Imc.     

NUCLEUS ISTHMUS OF TOAD IS SECONDARY VISUAL CENTER

Visual responses of 148 units have been recorded with micropipettes from the left nucleusisthmus areas of toads (Bufo bufo gargarizans), their auditory and tactile responses also exa-mined, and 122 recording sites marked with cobalt sulphide. This study indicates that: (i) 118units responding solely to visual stimuli are found within the nucleus, and 4 multisensory unitsoutside, (ii) there exist a visual field map and binocular units in the nucleus, and (iii) res-ponse latencies of the isthmic units to a spot of light range from 120 to 540 msee, with nocorrelation with recording sites.     

蟾蜍的峡核是次级视觉中枢

从中华大蟾蜍(Bufo bufo gargarixans)峡核区域记录了148个视觉单位,检验了它们对声和触刺激的反应,并用硫化钴标记出其中122个记录位置。结果指出:(1)118个只对视刺激有反应的单位在峡核内,4个多感觉单位在核外;(2)峡核内有个视野对应投射图和双眼单位;和(3)峡核单位对光点的反应潜伏期为120—540毫秒,和记录位置无关。