Polarization rotation in asymmetric periodic loaded rib waveguides

Abstract

A new mechanism for polarization rotation in rib waveguides is suggested and demonstrated in InP waveguides. The polarization rotation is achieved by loading a rib waveguide in a periodic asymmetric way. Complete TE↔TM conversion, with only 2–3 dB excess loss, is obtained in a 3.7-mm-long InP loaded waveguide. Strong polarization rotation (80%), in shorter devices (0.3 mm long), is also demonstrated.

Photonic Crystal for Polarization Rotation

“…Several structures of longitudinally variable passive polarization rotators have been reported in literature including: periodic asymmetric loaded rib waveguide (Shani et al, 1991), periodic tilted waveguiding section (Heidrich et al, 1992), periodically loaded strip waveguide (Mertens et al, 1998), cascaded bend waveguides (Van Dam et al, 1996;Liu et al, 1997Liu et al, , 1998aLiu et al, , 1998b) and a mode-evolution-based polarization rotator structure (Watts et al, 2005).…”

“…According to Fig. 1(b), the transverse component of the normal modes of for example the asymmetric loaded rib waveguide (Shani et al, 1991) …”

Silicon-based on-chip multiplexing technologies and devices for Peta-bit optical interconnects

“…In [139,140], the structure with periodical sections of asymmetrical load is used to realize a PR which is quite long (~3 mm) and has a large excess loss due to the scattering as well as the mode-mismatching at the junctions between alternating sections. Similarly cascaded bent sections have also been used [141,142] the PR length is as short as ~60 μm with the assistance of slant waveguide sidewalls [141].…”

Numerical Study on Fabrication Tolerance of Half-Ridge InP Polarization Converters

“…Various types of PCs have been demonstrated to date; those based on periodic loaded waveguides [5], microbended waveguides [6], adiabatic waveguides [7]- [10], and asymmetric waveguides [11]- [19]. The asymmetric PCs are suitable for monolithic integration with InP photonic devices as well as their short operating length and relatively small sensitivity against the deviation of the wavelength and the temperature.…”