Electrically tuneable lateral leakage loss in liquid crystal clad shallow-etched silicon waveguides.

Tuning the lateral leakage loss of TM-like modes in shallow-etched waveguides using liquid crystals.

We examine the tuning effect a liquid crystal (LC) cladding has on the lateral leakage loss of TM-like modes in shallow-etched waveguides. For such waveguides with an air cladding, the guided TM-like mode and the unguided cladding TE-like mode can only be phase matched at precisely one angle. We find that for an anisotropic cladding such as an LC, this phase matching is now possible for a range...

Characterizing the effects of free carriers in fully etched, dielectric-clad silicon waveguides

A design method of lithium niobate on insulator ridge waveguides without leakage loss.

We evaluate structural dependency of leakage losses in lithium niobate on insulator ridge waveguides. Generally, shallow ridge waveguides based on isotropic materials have inherent leakage loss for TM-like mode. On the other hand, lithium niobate is anisotropic material, thus the optical properties of lithium niobate based ridge waveguides are different from those of isotopic material based rid...

Transmittance of a tuneable filter at terahertz frequencies

A metallic photonic crystal filter has been demonstrated at terahertz frequencies, with the passband tuneable over the range 365 386 GHz. Tuning is achieved by a relative lateral shift of two metallic photonic crystal plates. Each plate comprises two orthogonal layers of gratings and integral mounting lugs. The plates are micromachined from silicon wafers then coated in gold to provide metallic...

Lateral leakage of TM-like mode in thin-ridge Silicon-on-Insulator bent waveguides and ring resonators.

We present the first prediction of lateral leakage behavior of the TM-like mode in thin-ridge SOI curved waveguides and ring resonators. A simple phenomenological model is first presented which predicts that the lateral leakage in these structures is significantly impacted by both the ring radius and waveguide width. This prediction is verified using full vectorial mode matching and finite elem...