The coupling characteristics of a hybrid coupler comprised of a long-range surface-plasmon-polariton (LRSPP) waveguide and a dielectric waveguide is analyzed with different detecting layers. Calculation results show that the coupling strength between the LRSPP mode and the dielectric-waveguide mode is rather sensitive to the refractive index of the detecting layer. This is promising to realize ...

We report the development of on-chip optical components designed to improve the out-coupling of double-metal terahertz (THz) frequency quantum cascade lasers (QCLs). A visible reshaping of the optical beam is achieved, independent of the precise waveguide configuration, by direct incorporation of cyclic-olefin copolymer (COC) dielectric optical fibers onto the QCL facet. A major improvement is ...

In a three-guide coupler with multimode central waveguide more than two modes of the entire structure participate in the coupling between the outer waveguides. Using a three mode approximation we found simple conditions for complete power transfer between the outer waveguides: the device length has to match certain multiples of the conventionally defined coupling length. The specific form of th...

An elastomeric grating coupler fabricated by the replica molding technique is used to measure the modal indices of a silicon-on-insulator (SOI) planar waveguide structure. Because of the van der Waals interaction between the grating mold and the waveguide, the elastomeric stamp makes conformal contact with the waveguide surface, inducing a periodic index perturbation at the contact region. The ...

In this paper, scattering and coupling problems of the directional coupler for the dielectric rectangular waveguides are analyzed by the mode-matching method in the sense of least squares for the fundamental mode incidence. This directional coupler is composed of three parallel dielectric rectangular waveguides cores which are placed at equal space in the dielectric medium. Namely, respective c...

On-chip polarization manipulation is pivotal for silicon-on-insulator material platform to realize polarization-transparent circuits and polarization-division-multiplexing transmissions, where polarization splitters and rotators are fundamental components. In this work, we propose an ultracompact and high efficient silicon-based polarization splitter-rotator (PSR) using a partially-etched subwa...

A prototype free-space-wave drop demultiplexer consisting of a cavity-resonator-integrated grating input/output coupler (CRIGIC) and a different-guided-mode-coupling distributed Bragg reflector (DGM-DBR) was designed for constructing a high-density wavelength-division-multiplexing intra-board chip-to-chip optical interconnection. The CRIGIC consists of one grating coupler and two DBRs, and can ...

The paper presents optical LAN topologies which are made possible using an Arrayed Waveguide Grating Multiplexer (AWGM) instead of a passive star coupler to interconnect stations in an all-optical LAN. Due to the collision-free nature of an AWGM it ooers the n-fold bandwidth compared to the star coupler. Virtual ring topologies appear (one ring on each wavelength) if the number of stations atta...

We demonstrate a novel scheme to control the excitation symmetry for an odd mode in a photonic crystal waveguide and investigate the spectral signature of this slow light mode. An odd-mode Mach-Zehnder coupler is introduced to transform mode symmetry and excite a high-purity odd mode with 20 dB signal contrast over the background. Assisted by a mixed-mode Mach-Zehnder coupler, slow light mode b...

In this paper, we present the design and experimental demonstration of a high dynamic range electric field sensor based on electro-optic (EO) polymer directional coupler waveguides that offers the strong and ultra-fast EO response of EO polymer. As compared to conventional photonic electric field sensors, our directional coupler waveguide design offers several advantages such as bias-free opera...