Wavelength-Tunable and OAM-Switchable Ultrafast Fiber Laser Enabled by Intracavity Polarization Control

Abstract

Ultrafast laser that directly emits vortex beam has broad application prospects in many research fields and applications, such as telecommunication, bio-sampling and quantum information science. In this article, we demonstrate a wavelength-tunable and OAM-switchable ultrafast fiber laser enabled by intracavity polarization controlling elements. The mode-locked laser can emit vortex beam outputs with a topological charge of l = +1 or l = -1 and the center wavelength can be continuously tuned from 1015nm to 1038nm. The obtained output pulse has a pulse energy of 3.3nJ and a compressed pulse duration of 87fs. Compared with previous results, this laser can emit OAM-switchable output with a shorter pulse duration and a broad wavelength tuning range. The concept of adding polarization control elements to a mode-locked fiber laser can be further expanded to build laser with more sophisticated and customizable outputs.

Orbital angular momentum mode femtosecond fiber laser with over 100 MHz repetition rate

“…将当前文献报道其他激光器性能和指标与本 文激光器进行了比较, 如表1所列, 按不同的模式 转换器分类如下: 错位熔接光纤(OSS) [31] 、熔融拉锥 耦合器(FBT) [27,32] 、长周期光纤光栅(LPFG) [33,34] 、 布拉格光栅(FBG) [35] 、声致光栅(AIFG) [36,37] , 以 及空间器件(Space) [38] . 通过以上的对比可知, 本 文OAM模式激光器的性能指标在全光纤型激光 器中有着更高重复频率, 更大光谱带宽, 更窄脉冲 宽度等优势, 是首个同时实现百兆赫兹重复频率、 纳米结构以及OAM光频梳等领域 [40] .…”