Wang Xiaozhen, Niedermayer Graeme, Lin Ganbin, Lu Ping, Wang Baishi, Chen Liang, Bao Xiaoyi
Fiber Optics Group, Department of Physics, University of Ottawa, Ottawa, Ontario, Canada.
Appl Opt. 2013 Mar 10;52(8):1550-4. doi: 10.1364/AO.52.001550.
Distributed group birefringence of tapered polarization-maintaining fibers (PMFs) is measured by employing a high-resolution optical frequency-domain reflectometry system. Autocorrelation data processing reveals distributed mode coupling between the fast and slow modes and higher-order modes excited by the tapering process along the taper region. The polarization-maintaining property of a tapered PMF is examined by distributed group birefringence along the tapered PMF with a spatial resolution of ~1.25 cm and a polarization-extinction ratio at the fiber taper output over the wavelength range of 1510-1570 nm. With a waist diameter of 80 μm, the polarization state of the launched light is maintained and the birefringence of the tapered PMF is slightly reduced from 3.28×10(-4) to 2.89×10(-4) at the taper waist. For both the waist diameters of 60 and 40 μm, mode coupling is observed in the form of significantly decreased birefringence by a factor of ~10 at the taper waists.
采用高分辨率光频域反射测量系统测量了锥形保偏光纤（PMF）的分布式群双折射。自相关数据处理揭示了沿锥形区域的锥形过程所激发的快模和慢模以及高阶模之间的分布式模式耦合。通过沿锥形保偏光纤的分布式群双折射来研究锥形保偏光纤的保偏特性，其空间分辨率约为1.25 cm，在1510 - 1570 nm波长范围内光纤锥形输出处的偏振消光比。腰径为80μm时，发射光的偏振态得以保持，锥形保偏光纤在锥形腰部的双折射从3.28×10⁻⁴略微降低至2.89×10⁻⁴。对于腰径为60μm和40μm的情况，在锥形腰部观察到模式耦合，表现为双折射显著降低约10倍。
