外腔半导体激光器的两种窄谱机制

本文区分和研究外腔半导体激光器的两种窄谱机制,从而简捷地得出了其线宽公式。本文的基本思想对于优化外腔半导体激光器的设计和探索新的外腔结构具有指导意义。     

半导体激光器参数的外腔法测量

通过测量运行在外腔中的半导体激光器的P-I(功率电流)曲线,可以确定二极管激光器的重要参量——吸收系数α、对电流的微分小信号增益系数dg/dI以及光子寿命等。     

894nm外腔半导体激光器

介绍了一种基于Littrow结构的894 nm外腔半导体激光器的设计原理,给出了光栅转轴的优化点计算,分析了无跳模范围和实际转轴位置的关系,指出了实际光栅转轴点的合理位置.针对铯原子激光抽运磁力仪的应用要求,通过外腔的选频功能,以及低噪声激光电流源、低温漂温控器和低噪声压电陶瓷驱动器,实现了自由运转波长为904 nm的...     

半导体激光器的输出模谱

利用半导体激光器多模速率方程组的隐式解析解，考虑到实际激光器的峰值增益波长与峰值谐振波长往往不一致的情况，从理论上对不同电流下半导体激光器的输出模谱进行了研究。     

外腔半导体激光器输出双稳环形状分析

研究了因折射率与载流子相互关联而引起的外腔半导体激光器的双稳特性，分析了不同条件下各种不同形状的载流子密度双稳环，计算了相应情况下的功率双稳环。     

复合双外腔半导体激光器

本文首次提出改进外腔半导体激光器性能必须同时满足两个条件:(1)振荡模要有最大的净增益;(2)振荡模与其相邻纵模间的净增益差足够大。据此理论研制成复合双外腔半导体激光器,首次在无任何反馈控制条件下实现了单模稳定运转时间大于24h、同一单模运转注入电流范围提高二个数量级,输出功率提高一个量级,其它各项性能也均有大幅度提高。     

外腔半导体激光器的线宽

本文用量子力学的方法求得了外腔半导体激光器(LD)的线宽,给出了抑制LD线宽的最佳反馈条件。     

光纤光栅外腔半导体激光器输出谱的射线法研究

本文采用射线法,计及增益随波长的变化,首次导出了光纤光栅外腔半导体激光器(FGESL)输出谱的表达式.利用该表达式,结合载流子速率方程,对FGESL输出谱的精细结构进行研究.研究结果表明:光纤光栅外腔将引起位于反射带宽附近波长处能量分布发生变化,在反射带宽内出现多峰结构,峰的数目与外腔长度有关;随着电流的增大,FGESL的输出功率和边模抑制比总体呈现上升的趋势,上升过程中存在波动,波动的幅度和频率随着前端面反射的减小而减小.     

利用偏振光谱对外腔式半导体激光器实现无调制锁频

将激光器输出频率相对于合适的参考频率标准进行锁定,可以有效地抑制激光器的频率起伏,提高激光器的频率稳定度。对铯原子偏振光谱进行平衡探测,当偏振光谱透射方向与偏振分束棱镜(PBS)偏振面之间的夹角选择合适时,平衡探测后的输出信号即为铯原子D2跃迁线的色散形鉴频信号。实验上实现了波长为852 nm的外腔式半导体激光器对应于铯原子6S1/2(F=4)→6P3/2(F′=5)超精细跃迁线的频率锁定。研究获得在50 s内激光器频率起伏小于±250 kHz,较相同时间内激光器自由运转时的频率起伏3 MHz有显著改善。这种频率锁定的方法不需要对激光器进行调制。     

可调外腔半导体激光器的绝对距离测量

提出了一种新型的可用于绝对距离测量的波长扫描光纤干涉仪。采用可连续调谐的外腔半导体激光器作为波长扫描光源。     

Theory of spectral linewidth of external cavity semiconductor lasers

A new formula of the spectral linewidth of external cavity semiconductor lasers is proposed, with which linewidth narrowing with the optical feedback is discussed. It is shown that in the limit of large external cavity length, the linewidth caused by the phase diffusion due to spontaneously emitted photons becomes dominant and the linewidth decreases proportionally to the inverse of the external cavity length.     

Narrowband external cavity laser diode arra

A laser diode array line narrowing using an external cavity with a holographic grating is demonstrated. A linewidth of 11 GHz is obtained at an operating wavelength of 852 nm with an output power of about 10 W. Narrow linewidth high-power diode arrays can be used to pump alkali lasers and to produce spin polarised noble gases     

高亮度半导体激光器无输出耦合镜光栅外腔光谱合束

宽面发射半导体激光器的光谱合束技术对发展高功率直接半导体激光光源具有重要意义。光栅外腔光谱合束基于光栅的波长选择特性和外腔半导体激光技术,实现单个合束单元的光谱锁定和所有合束单元的合束输出,输出光束质量与单个合束单元相当,而亮度和功率得到很大的提高。基于无输出耦合镜光栅外腔光谱合束结构,实现了单个半导体激光短阵列的光谱合束,分析了光谱合束的输出光谱、输出功率和光束质量的特性,获得了70 A工作电流下40.8 W的连续输出功率,快轴和慢轴方向的光束质量分别为0.41 mmmrad和9.16 mmmrad （包含95%能量）,相应的电光转换效率为38.4%,亮度高达67.90 MW/（cm2sr）。     

Extremely narrow spectral linewidth and low chirping of theMQW-DFB-PPIBH laser diode

The low threshold current of 9 mA, the high side-mode suppression ratio of more than 45 dB, the extremely narrow spectral linewidth of 1.1 MHz, and the low chirping of 2.8 Å at -20 dB at 2 Gb/s nonreturn to zero (NRZ) modulation have been achieved in the multiple quantum well (MQW) distributed feedback (DFB) p-substrate partially inverted buried heterostructure (PPIBH) laser diode. The spectral linewidth of 1.1 MHz is the narrowest value among 300-μm-length solitary laser diodes. These results suggest that the MQW-DFB laser diodes are a promising light source for longer distance and higher bit-rate optical communication systems and coherent optical communication systems     

Compact external cavity diode laser for quantum experiments

We present a compact and practical scheme of building a ~780 nm external cavity diode laser (ECDL) whose wavelength is mainly determined by an interference filter. The Lorentzian linewidth measured by the heterodyne beating between two identical lasers is 60 kHz, and the geometry size of the laser is only 71.5 mm×65 mm×40 mm. The linear cavity design is less sensitive to misalignment induced by mechanical and thermal disturbances, and in comparison to a common grating-based design, the sensitivity to vibration is substantially reduced. Due to its excellent performance, the laser design has already been applied to cold atom trapping experiments. This interference filter ECDL method can also be extended to other wavelengths and widen the application range of diode laser.     

Frequency stabilization of an external cavity laser diode usingelectrooptic effect

An external cavity laser diode, which consists of a LiNbO₃ phase modulator, was frequency-stabilized to a resonance frequency of a Fabry-Perot interferometer using the electrooptic effect. The optical frequency fluctuation was detected through a Fabry-Perot interferometer and the detected signal was negatively fed back to the phase modulator to reduce the frequency fluctuation. The rear facet of the electrooptic phase modulator was coated with gold and used as an external mirror. At feedback-off state, the peak-to-peak frequency fluctuation of the laser diode was 52 MHz in 2 min. At feedback-on state, the peak-to-peak frequency fluctuation was reduced to 1.5 MHz. This condition was maintained for the duration of the observation, 1 h and 40 min     

A 250 Hz spectral linewidth 1.5 mu m MQW-DFB laser diode with negative-electrical-feedback

A 1.5 mu m corrugation-pitch-modulated MQW-DFB laser diode (LD) with multielectrodes was frequency stabilized using the negative electrical feedback technique. The FM response of the LD was precisely measured and used for the feedback loop design. The FM noise of the LD was reduced and reached 10 Hz/sup 2//Hz at 1 kHz>     

外腔半导体激光器的高精度双稳温度控制

温度对于外腔半导体激光器的特性有很大的影响,对其温度进行高精度的控制,是保证外腔半导体激光器输出波长稳定的关键技术之一。本文介绍了外腔半导体激光器的高精度温度控制原理和方法,提出了采用PID控制原理的模拟电路设计和以单片机为核心的数字电路设计相结合的双稳温度控制方案,并对其进行了理论分析和实验研究。