报道了一种由ZnO纳米棒和CuCr_1－xMg_xO₂薄膜组成的新型紫外光电探测器。采用溶胶凝胶法制备CuCr_1－xMg_xO₂薄膜后在水热条件下生长ZnO纳米棒，然后使用扫描电子显微镜、X射线衍射仪以及分光光度计对CuCr_1－xMg_xO₂/ZnO的形貌、结构和吸收特性进行表征，研究了CuCrO₂/ZnO和CuCr_1－xMg_xO₂/ZnO探测器的紫外光电探测性能。紫外探测实验结果表明：该探测器具有快速响应特性，在－10 V测试电压下的光暗电流比约为CuCrO₂/ZnO的2.6倍，响应度相比CuCrO₂/ZnO提高了2.3 A/W。CuCr_1－xMg_xO₂/ZnO探测器具有优良的探测性能，而且制备工艺简单，成本低，可批量生产，是一种性能优良的光电探测器，在紫外检测方面具有多种应用。

A double-clad Yb-doped mode-locked fiber laser that can operate in burst-mode and square-pulse states is experimentally investigated. In the burst-mode state, a burst train with 55 pulses of 500 ps duration is obtained. In the square-pulse state, which is similar to noiselike pulses, the maximum pulse energy is 820 nJ and the duration can be tuned from 15.8 to 546 ns. The square pulses have a narrow and multipeak spectrum, which is quite different from that of normal noiselike pulses. The fiber laser promises an alternative formation mechanism for burst-mode and square-pulse mode-locked fiber lasers.

In high power laser beam parameters measurement, attenuation scheme with high rate is key to far-field measurement. The far-field optical measurement system was analyzed and diameter of 95% encircled energy was used as important evaluation criterion of far-field measurement system. Measurement error of far-field optical measurement system and effect of attenuation with high rate on far-field measurement results were analyzed. Principle of attenuation scheme with high rate was established. By changing parameters of high attenuation rate in condition of single parallel plate, a pair of parallel plates and a pair of wedge flaps by Virtual Lab, influence of attenuation on the far-field measurement system was simulated and analyzed deeply. According to measurement system for f=3 000 mm and F=10, best attenuation scheme with high rate is designed. Diameter of 95% encircled energy of far-field image is 45.5 ?滋m, or 3.54 times of diffraction limitation.

In high power laser beam parameters measurement, attenuation scheme with high rate is key to far-field measurement. The far-field optical measurement system was analyzed and diameter of 95% encircled energy was used as important evaluation criterion of far-field measurement system. Measurement error of far-field optical measurement system and effect of attenuation with high rate on far-field measurement results were analyzed. Principle of attenuation scheme with high rate was established. By changing parameters of high attenuation rate in condition of single parallel plate, a pair of parallel plates and a pair of wedge flaps by Virtual Lab, influence of attenuation on the far-field measurement system was simulated and analyzed deeply. According to measurement system for f=3 000 mm and F=10, best attenuation scheme with high rate is designed. Diameter of 95% encircled energy of far-field image is 45.5 ?滋m, or 3.54 times of diffraction limitation.

A method of controlling spectrum based on all-fiber multi-pass phase modulation is demonstrated experimentally and theoretically. Numerical simulation results indicate that modulation times, modulation depth, shape and width of the modulation signal and synchronized precision between optical pulse and modulation signal have influences on the central wavelength, bandwidth as well as the shape of the output spectrum. The input spectrum with bandwidth of 0.03 nm is broadened into 2.238 nm after multi-pass phase modulation, and the experimental results match well with the simulation results. The corresponding relationship between the modulation signal waveforms with different phases and the output spectra is obtained, and the feasibility of the spectral characteristics control is verified.

提出了一种基于全光纤多程相位调制的光谱控制方法，并对其进行了理论模拟和实验研究。理论模拟结果表明，调制次数、调制深度、调制信号形状和宽度以及调制信号和光脉冲的时间同步均会对输出光谱的中心波长、光谱宽度和形状产生影响。在实验上对光谱宽度为0.03 nm的注入信号进行多程相位调制，得到了带宽为2.238 nm的输出光谱，实验结果与理论模拟结果相符合。并从实验上研究了不同相位调制信号波形与输出光谱的对应关系，验证了通过控制调制信号波形进行光谱特性控制的可行性。