基于双折射效应设计了一种新型的双椭圆纤芯光子晶体光纤(PCF)偏振分束器，通过在每个纤芯处引入一对大空气孔和一对小空气孔来构成椭圆纤芯。采用全矢量有限元法(FEM)和半矢量光束传播法数值模拟偏振分束器的性能，结果表明，在工作波长1.55 μm处，光纤长度为544 μm时，X、Y方向偏振光可实现分离，且消光比达到-43.75 dB，消光比小于-10 dB的带宽为80 nm。这为设计具有高消光比和极短长度的双芯光子晶体光纤偏振分束器提供了一种新的结构。

Based on the birefringence effect, a novel polarization splitter based on dual elliptical-core photonic crystal fiber (PCF) is proposed, the elliptical-core through introducing a pair of big air holes and a pair of small air holes in every core. The full-vector finite element method (FEM) and the semi-vector beam propagation method (BPM) are employed to analyze the performance of the splitter. Numerical simulations demonstrate that it is possible to obtain a 544 μm long polarization splitter, and the polarized light extinction ratio is -43.75 dB at the wavelength of 1.55 μm. Besides, the bandwith is over 80 nm when the extinction ratio is less than -10 dB. Such design provides a new approach to get highly extinction ratio and short length polarization splitter based on dual-core photonic crystal fiber.