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预脉冲灯泵钛宝石可调谐激光器   总被引:1,自引:0,他引:1  
利用预脉冲技术,可减小氙灯放电初始阻抗,使主放电电流脉冲前沿变陡,脉冲包络变窄,峰值变高,泵浦能量集中,有利于灯泵钛宝石激光输出。试验证明,在低能量(47J)注入时,电光转换效率提高18%,输出950mJ;在高能量(116J)注入时,效率提高5%,输出能量1810mJ。该激光器可调谐范围为695~940nm。  相似文献   
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介绍了几种提高灯泵钛宝石激光器效率的技术途径,包括脉冲氙灯参数的选取,放电电流的优化,泵浦腔几何结构的设计,光学谐振腔参数的优化和输出耦合镜最佳透过率的选取。通过以上各项技术的完善,激光效率得到明显提高,从0.5%到2%[1]。  相似文献   
3.
InGaAs/GaAsP strain-compensated multiple quantum wells (SCMQWs) and strained InGaAs/GaAsmultiple quantum wells (MQWs) were grown on GaAs substrates by metal organic vapor phase epitaxy(MOVPE). The results of double crystal X-ray diffraction (DCXRD) revealed that strain relief had beenpartly accommodated by the misfit dislocation formation in the strained MQW material. It led to thatthe full width half maximums (FWHMs) of superlattice satellite peaks are broader than those of SCMQWstructures, and there was no detectable room temperature photoluminecence(RT-PL)for the strained  相似文献   
4.
闪光灯泵浦钛宝石可调谐激光器   总被引:1,自引:0,他引:1  
为了提高灯泵钛宝石激光器的输出能量和效率,对灯泵钛宝石激光器进行了大量的试验研究工作。对国产氙灯进行了快速放电和寿命试验;测得了在不同放电电流密度情况下的氙灯发光光谱分布;试验采用双灯串接泵浦,双棱镜色散光学谐振腔,平平腔型,调谐范围为750~950nm,在中心波长800nm处得到激光输出能量为893mJ,电光转换效率为0.89%。该激光器的阈值约为15J。  相似文献   
5.
磷化物半导体纳米材料的合成和表面性质   总被引:3,自引:0,他引:3       下载免费PDF全文
在低温(80~100℃)常压下用Na3P分别和GaCl3,InCl3反应制备了GaP,InP纳米材料,对材料的物相结构和微观形貌进行了表征. 研究了GaP纳米晶体在氮气中的表面反应活性,该纳米晶体的重量在370~480℃之间会增加,可以认为氮气分子被吸附在了GaP纳米晶体的表面并发生了活化反应.  相似文献   
6.
Gap and InP nanocrystals were synthesized from Na3P and GaCI3 at low temperature (80–100°C) and atmospheric pressure. The samples were characterized by XRD and TEM measurements. The surface reactivity of Gap nanocrystals was studied by heating in N2. The weight of the nanocrystals increased at the temperature between 370°C and 480°C. It can be concluded that N, molecule was absorbed and reactivated on the surface of Gap nanocrystals. Keywords: gallium phosphide, indium phosphide, nanocrystal, surface reactivity.  相似文献   
7.
For both BiSrCaCuO and TlBaCaCuO samples, internal frictions (Q-1) in the kHz range reveal a plateau (Q-1p) above Tc and a rapid drop below Tc with the turning points located just at Tc for various samples with different Tc. This anomaly cannot be observed in non-superconducting samples. The ultrasonic attenuation (α) in TlBaCaCuO displays similar results to the internal friction. Moreover, it is discovered that the Q-1p is nearly proportional to the carrier density for Y(Pr)BaCuO and Gd(Pr)BaCuO with different Pr contents. These results show that the drop of Q-1 and a below Tc is closely related to superconducting condensation. The Q-1p and αp can be explained using coupling-model of carriers with local dynamic distortion because high Tc superconductors are strong-correlation systems. Furthermore, by taking account of the smearing of superconducting gap structure resulting from the recombination of quasi-particles and by modifying the BCS relative jump rate as S(E, E', Γ) = Re{1-Δ2/[(E-iΓ)(E'-iΓ)]}, the calculated results of internal friction and ultrasonic attenuation below Tc are in good agreement with the experimental data. The superconducting gap Δ and the damping rate Γ for both BiSrCaCuO and TlBaCaCuO have also been obtained, they are in accordance with those got by tunneling spectrum and NMR methods, etc.  相似文献   
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