Pressure-assisted low-loss fusion splicing between photonic crystal fiber and single-mode fiber.

We demonstrate low-loss splicing between a photonic crystal fiber (PCF) and a single-mode fiber (SMF) with a conventional electric-arc fusion splicer, where nitrogen gas (N) with a proper pressure is pumped into the air holes of the PCF to control the air-hole collapse ratio so as to optimize the mode-field match at the joint. The method is applicable to both solid-core and hollow-core PCFs. With this method, we achieve a splice loss (measured at 1550 nm) of ~0.40 dB for a solid-core PCF and ~1.05 dB for a hollow-core PCF. The method could find wide applications in the fabrication of PCF-based devices.