设计并制作了一种光纤微悬臂梁传感器，由于悬臂梁在受迫振动过程中不会产生拉伸变形，与四周固定的圆形密闭薄膜相比，会产生更高的声波灵敏度。采用飞秒激光加工制作微悬臂梁薄膜光纤声波传感器，制备出长宽均为500 μm，厚6 μm的微悬臂梁结构。通过实验得到其反射光谱对比度为8.8 dB，自由光谱范围为7.72 nm，理论计算得光纤法布里-珀罗腔长为155.6 μm。研究结果表明，该光纤声波传感器在2 200 Hz处出现明显的共振峰，对应的声压灵敏度为414 mV/Pa，在300 Hz时有最大的灵敏度675 mV/Pa，与普通硅橡胶薄膜声波传感器相比灵敏度显著提高。理论计算硅橡胶微悬臂梁光纤声波传感器的一阶共振频率为198 Hz，与实验测得的共振频率较为接近。同时悬臂梁传感器的声压灵敏度可达675 mV/Pa，声压响应线性度为0.994。

Supercontinuum generation (SC) of more than one octave spectrum spanning covering from 400 nm to 820 nm was achieved by pumping a piece of aluminum nitride (AIN) single crystal using a nanosecond 355 nm ultraviolet laser. The AlN with a thickness of ～0.8 mm was grown by an optimized physical vapor transport technique and polished with solidification technology. Compared to previously reported ones, the achieved visible SC exhibited the broadest spectrum spanning from bulk materials pumped by a nanosecond pulse laser. The visible supercontinuum in AlN presents new opportunities for bulk material-based white light SC and may find more potential applications beyond typical applications in integrated semiconductive photoelectronic devices.

We report a Q-switched self-Raman third-Stokes laser at a wavelength of 1487 nm, with a YVO4/Nd:YVO4/YVO4 composite crystal and a high-power fiber-coupled diode laser array at 808 nm. The maximal average output power at 1487 nm is measured to be 506 mW, at an incident pump power of 34 W and a pulse repetition frequency (PRF) of 30 kHz. The corresponding optical conversion efficiency is 1.49%. To our knowledge, our Q-switched self-Raman third-Stokes laser at 1487 nm on a YVO4/Nd:YVO4/YVO4 composite crystal is reported for the first time.