3D打印机械光栅挤压涡旋光纤激发矢量模

Excitation vector modes by applying stress on vortex fiber through an external 3D printed mechanical grating

为了克服传统的光栅刻写技术对光纤造成不可逆转的损害的缺点,提出了一种3D打印长周期机械光栅的方法。在施加适当压力的情况下,该方法可以将涡旋光纤中的基模(HE_(11))转化为矢量模式(TM_(01)、HE_(21)、TE_(01));在谐振波长处,通过调整输入涡旋光纤的基模偏振态,可以得到较高纯度的矢量模式;在涡旋光纤上安装一个偏振控制器,使HE_(21)偶模与奇模之间产生π/2或者-π/2的相位差,得到了±1阶轨道角动量(OAM)模式,并通过其与高斯光的干涉图案进行了验证。实验结果表明,该方法具有简单灵活、成本低廉和对光纤损伤小等优点。

In order to overcome the shortcomings of traditional grating technology in irreversible damage to optical fibers, a method for printing 3D long period mechanical gratings is proposed. In the case of proper pressure, the method can convert the base mode（HE11） into vector mode（TM01, HE21, TE01） in the vortex fiber,and the high purity vector mode can be obtained by adjusting the basic mode polarization state of the input vortex fiber at the length of the resonant wave. With the help of polarization controller, the phase difference between even mode of HE21 and odd mode of HE21 equals to π/2 or-π/2 can be achieved, and the generation of OAM modes with =±1 order are confirmed by their interference pattern with Gauss beam. This method is simple and flexible, low cost, little damage to optical fiber and so on.