Broadband single-polarization optical fiber based on surface plasmon resonance

We present, to the best of our knowledge, a new scheme of broadband single-polarization optical fiber with high extinction ratio based on surface plasmon resonance (SPR). The double-hole optical fiber with a Ge-doped core is modified by integrating the stacks of conductive and dielectric layers to support SPR. The strong couplings between the guided modes and surface plasmon mode can bring about serious polarization loss of TM mode, while supporting the efficient transmission of TE polarization in broadband. The achievable extinction ratio can be more than 25 dB covering a wide telecom band of 1.17–1.42 µm in short fiber l e n g t h s = 2.5 m m . Meanwhile, the insertion loss of the fiber is less than 0.25 dB. The modified SPR fiber shows promising application in high-quality fiber-integrated polarizers.