Ultra-compact, low-loss,TE- and TE-compatible mode waveguide bends.

Waveguide bends have become an interesting research direction because they allow highly curved light transmission in a limited space. Here, we propose waveguide bends supporting two TE modes by etching slots and adding germanium arcs in the inner side of a waveguide bend. Simulations show that the bending radius of our proposed base-mode waveguide bend drops to 500 nm and its insertion loss (IL) is reduced to 0.

On-chip multifunctional polarizer based on phase change material.

Polarizers are used to eliminate the undesired polarization state and maintain the other one. The phase change material (GSST) has been widely studied for providing reconfigurable function in optical systems. In this paper, based on a silicon waveguide embedded with a GSST, which is able to absorb light by taking advantage of the relatively large imaginary part of its refractive index in the crystalline state, a multifunctional polarizer with transverse electric (TE) and transverse magnetic (TM) passages has been designed.

Reconfigurable TE-pass polarizer based on lithium niobate waveguide assisted by GeSbTe and silicon nitride.

On-chip polarization management components play a critical role in tackling polarization dependence in the lithium-niobate-on-insulator (LNOI) platform. In this work, we proposed a reconfigurable TE-pass polarizer based on optical phase change material (GST) and the LNOI wafer. The key region is formed by a hybrid GST- layer symmetrically deposited atop the centerline of the LNOI waveguide along the propagation direction where the GST is sandwiched in the middle of the layer.

On-Chip Reconfigurable and Ultracompact Silicon Waveguide Mode Converters Based on Nonvolatile Optical Phase Change Materials.

Reconfigurable mode converters are essential components in efficient higher-order mode sources for on-chip multimode applications. We propose an on-chip reconfigurable silicon waveguide mode conversion scheme based on the nonvolatile and low-loss optical phase change material antimony triselenide (SbSe). The key mode conversion region is formed by embedding a tapered SbSe layer into the silicon waveguide along the propagation direction and further cladding with graphene and aluminum oxide layers as the microheater.