研究了硬边环带光阑内外半径和衰减因子对环带光阑圆形艾里光束(CAB)自聚焦特性的影响。结果表明,控制环带光阑内外半径,可以增加CAB第一个自聚焦峰光强且抑制传播后续聚焦峰光强;和无光阑时相比,添加环带硬边光阑有聚焦峰光强在不同的衰减因子下普遍增强的优点。因此,该方法在光操控粒子方面具有潜在的应用。

利用光学注入锁定制备的拉曼激光可以用于原子干涉仪。为解决原子干涉条纹的相位受相位噪声的极大影响的问题,研究了不同实验条件下的拉曼激光相位噪声。采用光纤电光调制(EOM)和注入锁定相结合的方法得到两束频差为6.834 GHz的相位锁定拉曼激光,将主激光通过光纤EOM移频 6.834 GHz后作为种子光注入到从外腔半导体激光器,调节从激光器,获得-1级移频光的初步放大激光。结果显示,拉曼激光的拍频线宽不大于3 Hz,频率可调范围为300 MHz,主激光锁频下相位噪声在10 Hz~100 kHz范围内低于-60 dBc/Hz。

Calcium is one prospective element for the modern optical frequency standard. The 423-nm transition line of calcium atoms has been widely used in laser slowing and laser cooling, the precise spectrum measurement, and the magnetic optical trapping (MOT). However, there is no any available commercial diode laser working at this wavelength. We built a 423-nm laser based on extra bow-tie cavity and by using a Brewster-cut uncoated BIBO (BiB3O6) crystal, which worked at room temperature, with conversion efficiency of 3.75%, and a potential up to 20%.