Low-Loss Patch Cords by Effective Splicing of Various Photonic Crystal Fibers With Standard Single Mode Fiber

We report on low-loss patch cords composed of a highly reproducible low-loss fusion splicing of photonic crystal fibers (PCFs) with a standard single mode fiber (SMF). Distinct from other papers in this area we report on the results for different types of PCFs, including LMA fibers with similar to a SMF core size and a mode field diameter (MFD), as well as polarization maintaining (PM) Bow-Tie PCF with an elliptical GeO
$_{2}$
doped core and also a suspended-core (SC) PCF with a tiny core. We show that all studied splices between SMF and PCFs exhibit dispersive and non-reciprocal, in view of a light propagation direction, transmission losses. Defined as a larger decrease of a transmitted optical power comparing both propagation directions, achieved splicing losses, are equal to
$0.46 \pm 0.03$
dB,
$0.34\pm 0.01$
dB,
$0.67 \pm 0.17$
dB and
$3.09 \pm 0.36$
dB at 1550 nm for LMA8, LMA10, Bow-Tie PCF and SC PCFs, respectively. Moreover, additionally to developed low-loss splicing, we report on low-loss patch cords for all mentioned above PCFs spliced on both ends with SMF pigtails ended with FC/APC connectors achieving the total losses at 1550 nm equal to
$1.07 \pm 0.07$
dB for LMA8,
$0.72 \pm 0.20$
dB for LMA10,
$1.30 \pm 0.06$
dB for Bow-Tie PCF, and
$9.36 \pm 0.20$
dB for SC PCF.