A Novel Gold Film-Coated V-Shape Dual-Core Photonic Crystal Fiber Polarization Beam Splitter Covering the E + S + C + L + U Band

In this paper, a novel gold film-coated V-shape dual-core photonic crystal fiber (V-DC-PCF) polarization beam splitter (PBS) based on surface plasmon resonance effect is proposed. The coupling lengths of the X-polarization (X-pol) and Y-polarization (Y-pol) and the corresponding coupling length ratio of the proposed V-DC-PCF PBS without gold film and with gold film are compared. The fiber structure parameters and thickness of the gold film are optimized through investigating their effects on the coupling lengths and coupling length ratio. As the propagation length increases, the normalized output powers of the X-pol and Y-pol of the proposed V-DC-PCF PBS at the three wavelengths 1.610, 1.631, and 1.650 [Formula: see text] are demonstrated. The relationships between the extinction ratio ([Formula: see text]), insertion loss ([Formula: see text]) and wavelength for the three splitting lengths ([Formula: see text]) 188, 185, and 182 [Formula: see text] are investigated. Finally, it is demonstrated that for the proposed V-DC-PCF PBS, the optimal [Formula: see text] is 188 [Formula: see text] , the [Formula: see text] of the X-pol and Y-pol are less than 0.22 dB, and the splitting bandwidth ([Formula: see text]) can cover the E + S + C + L + U band. The proposed V-DC-PCF PBS has the ultra-short [Formula: see text] , ultra-wide [Formula: see text] , and ultra-low [Formula: see text] , so it is expected to have important applications in the laser, sensing, and dense wavelength division multiplexing systems.