基于体光栅的被动锁模可调谐线型腔掺镱光纤激光器

Wavelength-tunable linear-cavity passively mode-locked Yb-doped fiber laser based on volume Bragg grating

搭建了基于反射型体光栅和半导体可饱和吸收镜的线型腔全正色散掺镱光纤激光器,室温下实现了稳定的波长可连续调谐的连续被动锁模脉冲输出.重复频率16.42 MHz,锁模脉冲中心波长1030 nm时,脉冲光潜带宽0.32 nm,最大平均输出功率10.2 mW,单脉冲能量0.63 nJ.转动体光栅角度,利用其分光谱和选波长的特性,可使锁模脉冲的中心波长在约1011.9一1050.6 nm的范围内调谐,调谐范围约38.7 nm.实验中亦可观察到调Q锁模、二次谐波锁模、双波长和三波长输出现象.输出单波长锁模脉冲时,由于其波长可调谐的特性,该激光器可用作波分复用/光时分复用通信系统的光源和光学相干层析的调谐光源.

The linear-cavity all-normal-dispersion Yb-doped fiber laser based on semiconductor saturable absorber mirror and reflection type volume Bragg grating （VBG） is demonstrated. A passively mode-locked pulse stable output with a 0.32 nm spectral bandwidth, a 10.2 mW maximum average output power, a single pulse energy of 0.63 nJ and a 16.42 MHz repetition rate is achieved, when the central wavelength of pulse is 1030 nm. The central wavelength of the pulse can be tuned approximately from 1011.9 nm to 1050.6 nm by the spectral separation and mode selection effect of VBG with a tuning range of 38.7 nm at room temperature. Q-switched, second harmonic mode-locked, simultaneous dual wavelength and triple wavelength output are observed. This mode-locked fiber laser can be used as the optical source in wave division multiplexing optical time division multiplexing communication system and optical source of optical coherence tomography due to its tunable wavelength.