北京自由电子激光器外注入实验系统设计研究

北京自由电子激光器(BFEL)是一台工作于中红外区Compton型FEL振荡器。本文结合BFEL装置,设计了一套完整的激光外注入光路,利用声光调QCO_2激光器产生的10.6μm激光做激励源注入到BFEL光腔中,以缩短振荡建立时间,提高BFEL输出能量,改善输出激光的相干性。模拟计算结果是:当BFEL光腔中的外注入光强为自发辐射强度的10~5倍时,可使饱和振荡建立时间缩短35％,输出能量提高2倍。     

Non-linear quasi-optical cell with polarized nuclear target (PNT) material

A resonance electromagnetic structure (a Fabry-Perot resonator) with a plane-parallel sample of the polarized nuclear target (PNT) material of a paramagnetic complex Na HMBA (Cr^V) is considered under condition of dynamic polarization of nuclear by millimeter waves. Non-linear effects observed at the electron spin resonance (ESR) in such structure have been studied. The results of the experiment with the quasi-optical resonance cell of the radiospectrometer designed for the investigation of the magnetic resonance in the millimeter wavelengths range are given. A hysteresis of the transfer coefficient of the cell in the ESR-line has been found while slow passing the ESR-line by retuning of the static magnetic field. The deformation of the form of non-stationary signals passed through the cell has been found.     

带受激布里渊散射池的位相共轭激光器输出的空间特性

本文应用传输矩阵的方法对受激布里渊散射位相共轭腔输出的空间特性进行了分析及编程计算，给出了各种参数下受激布里渊散射－位相共轭腔的传输光束轮廓图，同时给出了实验结果与之相比较，提出了设计受激布里渊散射共轭腔时应注意的问题及几种实用的受激布里渊散射位相共轭腔的腔型。     

Millimeter Waveband Resonator Cell of Scanning ESR-Spectrometer

The analysis of the resonator cell of Electron Spin Resonance (ESR) spectrometer, capable of studying the plane-film specimens in millimeter waveband is presented. Static magnetic field in 15 m×0.75 mm working zone is created by the magnetic field concentrator unit of special design. Mechanical shifting of the concentrator provides scan of the magnetic field on the speicmen surface. The experimental measurements of the magnetic field strength in the working zone give possibility to carry out the ESR experiment in the wavelength band 4-7mm.     

适用于硅微谐振器件测量的光纤位移传感器研究

对一种适用于硅微机械谐振器件测量的光纤位移传感器进行了研究,该光纤位移传感器探头采用了单根光纤探测形式和光纤“X”耦合器结构,在微弱光电传感信号处理上采用了“锁相放大器”提取方案,可以实现对静态位移和振动位移两种场合进行测量.对该传感器的实测结果表明:该传感器测量范围为0～100 μm,测量灵敏度3.95 mV/μm,精度等级优于1%,重复性优于0.5%.为作为应用实例,运用该传感系统对一种微悬臂梁硅微谐振器件进行了测量,成功提取了硅微谐振器件的微弱谐振信号,证实了该传感器可以实现对硅微谐振器件的非接触和无损测量,并具有非接触、易调试、高灵敏度等优点.     

Suppression of Chaotic Generation Caused by the External Optical Feedback in a Laser Diode

It is shown by computer simulation and in experiments that chaotic generation caused by the external optical feedback in a laser diode can be suppressed by means of a delayed optoelectronic feedback controlled by the injection current. The suppression of chaotic generation is realized for an AlGaAs/GaAs laser of the quantum wall structure. In the presence of the external optical feedback provided by the mirror placed at a distance of 1~mm the noise of optical intensity is of the oder of 10 W, the single mode dominates in the spectrum, and its spectral width exceeds 600 MHz. The optoelectronic feedback controlled by the injection current reduces the noise by several times and narrows the generation line width down to 80 MHz.     

90°束旋转环形非稳腔几何特性分析

分析了ＵＲ９０环形非稳腔（ＵｎｓｔａｂｌｅＲｅｓｏｎａｔｏｒｓｗｉｔｈ９０°ＢｅａｍＲｏｔａｔｉｏｎ）正向模和反向模的几何特性，讨论了反向模无阻挡时的振荡条件，并导出了理想ＵＲ９０环形非稳腔的光线追述方程，考查了此腔对激光增益介质的空间自平均效应。     

Study on transient mode formation of copper vapor laser with a modified off－axis unstable resonator

Ｓｔｕｄｙ ｏｎ ｔｒａｎｓｉｅｎｔ ｍｏｄｅ ｆｏｒｍａｔｉｏｎ ｏｆ ｃｏｐｐｅｒ ｖａｐｏｒ ｌａｓｅｒ ｗｉｔｈ ａ ｍｏｄｉｆｉｅｄ ｏｆ ｆ－ａｘｉｓ ｕｎｓｔａｂｌｅ ｒｅｓｏｎａｔｏｒ￥ＨＵＡＲｅｎｚｈｏｎｇ；ＬＩＡＮＧＰｅｉｈｕｉ；...     

Microwave magnetic resonance in some quick-hardened metal glasses

Development of research technique of magnetoresonance properties in a mm radiowave range is represented. The paper gives experimental data for metal glasses based on Fe and Co, and new substances, demonstrating magnetic phase transitions at the low temperature.     

北京自由电子激光装置的红外激光振荡实验

本文阐述了北京自由电子激光装置所采取的优化电子束质量等措施以满足出光条件,和利用这台装置相继观察到了自发辐射、储存自发辐射和受激辐射的情况.测定的受激辐射讯号的强度、光谱、失谐曲线和波长移动均证明其为红外自由电子激光振荡讯号.