Passive polarization converter in SiON technology

Abstract

Abstract-A passive polarization converter has been realized in silicon oxynitride (SiON) technology. The device is a grating assisted codirectional coupler consisting of segments of asymmetrically etched ridge waveguides. By using a double-masking technique, the fabrication of the device is tolerant with respect to the alignment of the required masks. Conversion efficiencies up to 0.98 (TE TM and TM TE) and insertion losses of 3 dB/cm have been measured. Using 2-D beam propagation method simulations, an observed beat pattern in the converter could be explained as due to a leaky mode, which is captured in the grating structure.

Design of polarization rotators in TE–TM mode conversion optical isolator with Ce:YIG guiding layer

“…25) A polyimide half-wave plate is inserted into a groove fabricated in the waveguide as the π=4-rad reciprocal polarization rotator. 8,9) As a waveguide-type device, a reciprocal polarization rotator can be realized through an electro-optic effect, 26) using a rib waveguide with a periodically asymmetric cross-section, 27) or by operating in a hybrid supermode. 28) Because the Cotton-Mouton effect 5,6) is not necessarily required for the reciprocal polarization rotator, the complicated control of the direction of the magnetization is no longer burdensome.…”

Optimized Gallium Arsenide Modulators for Advanced Modulation Formats

“…Generally, only a narrow, deep-ridge waveguide can be made nonbirefringent [31] and the width must be set with extremely high precision. The new polarization axis can then be established by means of a physical asymmetry such as a deeper etch at one side of the ridge [32] or a slanting sidewall [33]. Where the asymmetry is insufficient to achieve fully hybrid modes (i.e., a 45 • axis) a periodic, multistage configuration is used.…”

An integrated optical platform for absorptive sensing of chemical concentrations using chemo-optical monolayers

“…Launching the lowest order TE 00 mode, a polarization converter is required for the partial mode conversion into a TM 00 mode. Within our material system, a polarization converter based on an asymmetrical ridge grating structure has been developed [13]. The layout of the structure is shown in figure 7.…”