  This work presents an integrated design of a multifunctional hexagonal
lattice dual-core photonic crystal fiber (DC-PCF) with elliptical air-hole
surrounding the cores, using two different chalcogenides (As2S3-Arsenic sulfide
and As2Se3-Arsenic selenide) for mid-infrared (mid-IR) optical communications.
Numerical study of both chalcogenide DC-PCF structures exhibits that the
DC-PCFs are highly birefringent and single-moded in the mid-IR wavelength
region (5 um to 13 um) of optical communications. Results show that both
DC-PCFs can be operated as polarization splitters at 9 um wavelength for two
orthogonal modes and they can also be used as WDM MUX-DeMUX for both X- and
Y-polarization fundamental supermodes separating 9 um/10 um wavelengths (As2S3
DC-PCF) and 8 um/9 um wavelengths (As2Se3 DC-PCF). Moreover, the proposed
chalcogenide DC-PCFs, with much lower splice loss at 8-10 um wavelength region,
are appropriate enough for the practical applications in integrated optics and
photonics.
