We present measurements of biomolecular binding reactions, using a new type of integrated-optical biosensor based on a planar directional coupler structure. The device is fabricated by Ag(+) - Na(+) ion exchange in glass, and definition of the sensing region is achieved by use of transparent fluoropolymer isolation layers formed by thermal evaporation. The suitability of the sensor for applicat...

Linear and nonlinear directional couplers are currently used in fiber optics communications. They may also play a role in multiphoton approaches to quantum information processing if accurate control is obtained over the phases and polarizations of the signals at the output of the coupler. With this motivation, the constants of motion of the coupler equation are used to obtain an explicit analyt...

Planar directional coupler using Substrate Integrated Waveguide technology (SIW) is proposed in this paper. The SIW coupler with tapered microstrip-SIW transitions are integrated on the same substrate. Planar form makes this coupler structure easily integrable in microwave planar circuits. These proposed power dividers can be applied to the design of the beam-forming network for communication s...

We experimentally demonstrate on-chip mode-selective wavelength conversions based on the degenerate four-wave mixing (FWM) nonlinear effect in a few-mode silicon waveguide. A multimode waveguide with tapered directional coupler based mode (de)multiplexers is designed and fabricated. Using signals with advanced modulation formats all-optical wavelength conversions of 102.6-Gb/s OFDM-QPSK signals...

TV combiner is a device which can be used to transmit two or more TV or FM programs with different frequencies and power levels by a single wide band antenna simultaneously. One of the following three methods is usually used for its construction: 1-Star Point Filters, 2-Directional Coupler Filters and 3Phase Line Method. In this paper, using phase line method which is simpler compared to other ...

A polarization splitter and rotator (PSR) based on a tapered directional coupler with relaxed fabrication tolerance is proposed and demonstrated on the silicon-on-insulator platform. The device is simply constructed by parallel-coupling a narrow silicon waveguide with a linearly tapered wider waveguide. Compared to previously reported PSRs based on a normal directional coupler, which suffer fro...

The visualization of an exceptional point in a PT-symmetric directional coupler (DC) is demonstrated. In such a system the exceptional point can be probed by varying only a single parameter. Using the Rayleigh-Schrödinger perturbation theory we prove that the spectrum of a PT-symmetric Hamiltonian is real as long as the radius of convergence has not been reached. We also show how one can use a ...

In this paper, we present the design and simulation of silicon-on-insulator (SOI) based integrated optic Directional Coupler. Planar waveguide devices based on SOI architecture offer attractive possibility of miniaturization because of the high difference in refractive index between Silicon and SiO2. It has been shown that this technology offers the ability to make devices with sharper bends wi...

─ A novel broadband 3-dB directional coupler design method utilizing HFSS and realization are given in this paper. It is realized in stripline, showing great agreement with the simulation and design format. The unique property of this design method is that it unnecessitates both a feedback from the realization for broadbanding and an additional smoothing of transition between coupled sections o...

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...