基于稀土掺杂石英光纤的单频光纤激光器

Single-frequency fiber laser based on rare-earth-doped silica fiber

系统研究了利用稀土掺杂的石英光纤作为激光增益介质来实现分布布拉格反射式单频光纤激光器。实验中,分别将掺有Nd^(3+)、Yb^(3+)、Er^(3+)/Yb^(3+)和Tm^(3+)的商用石英光纤,熔接到激光谐振腔中,实现了基于石英玻璃光纤的光纤激光系统在多波段的单纵模运转。对各光纤激光器的单频特性进行了研究,其中,激光器线宽可达几十千赫(特别是对于Er^(3+)/Yb^(3+)共掺光纤激光器,其线宽窄于7 kHz),激光系统的强度噪声接近于散粒噪声极限,实验中获得了激光波长由930 nm到2μm的单频光纤激光器。实验结果证明:商用的稀土掺杂石英光纤能够作为有效的增益介质来实现短腔型单频光纤激光器。同时,通过进一步的系统集成,基于稀土掺杂石英光纤的单频光纤激光器将得到更加广泛的应用。

Single-frequency distributed Bragg reflector （DBR） fiber lasers were systematically investigated with rare-earth-doped silica fibers. The commercial Nd3＋, Yb3＋, Er3＋/Yb3＋ and Tm3＋-doped silica fibers were applied in this demonstration to achieve the monolithic all-silica glass fiber lasers operating on single longitudinal mode. In the experiment, single-frequency operation was characterized, linewidth of tens of kilohertz was obtained （especially for the Er3＋/Yb3＋ co-doped fiber laser, the linewidth was narrow to 7 kHz） and the measured relative intensity noise approached the shot noise limit. The result confirms that commercial rare-earth-doped silica fiber can be an efficient gain medium to achieve single-frequency fiber laser with the wavelength range from 930 nm to 2 μm, which can be further commercialized for a wide range of applications.