A novel solution of broadband asymmetric multisection coupled-line directional couplers has been proposed in which the required coupling of the tightlycoupled section is reduced. The coupling coefficient reduction has been achieved by the appropriate connection of a tightly-coupled section which has been rotated and connected with the remaining sections in such a way that the transmission and c...

We report that the complex conjugate artifact in Fourier domain optical coherence tomography approaches (including spectral domain and swept source OCT) may be resolved by the use of novel interferometer designs based on 3x3 and higher order fiber couplers. Interferometers built from NxN (N>2) truly fused fiber couplers provide simultaneous access to non-complementary phase components of the co...

Insertion loss is an important parameter used to characterize passive fiber-optic components, such as WDM couplers and variable optical attenuators. This article describes an automated insertion loss measurement system which incorporates 980 nm, 1310 nm, 1529 nm and 1561 nm DFB lasers and two internal fiber optic standards. Insertion loss measurements collected with the system for WDM couplers ...

There is a great deal of interest and activity in the area of femtosecond micromachining of transparent materials. It promises to be a powerful technique for rapid fabrication of photonic devices in three dimensional geometries. Our group has fabricated and investigated an array of two dimensional and novel three dimensional photonic devices that are able to perform their intended functions but...

A four-channel wavelength multiplexer/demultiplexer for sparse wavelength division multiplexing was demonstrated using cascaded three-dimensional ~3D! vertical couplers. 17 nm channel spacing with crosstalk less than 15 dB was achieved. Strong coupled vertical couplers were fabricated using wafer bonding to invert a conventionally processed epitaxial layer and bond to a new host substrate. This...

Thin film integrated optics components such as light guides, modulators, directional couplers, and polarizers demand high quality edge smoothness and high resolution pattern formation in dimensions down to submicrometer size. Fabrication techniques combining holographic and scanning electron beam lithography with ion beam micromachining have produced planar phase gratings with intervals as smal...

We deal with second-harmonic generation in chi((2)) nonlinear-optical resonators such as prism or grating couplers. The theoretical study is performed within the framework of a recently developed coupled-mode analysis leading to a set of equations governing the amplitudes of pump and second-harmonic frequency fields. We predict analytically that second-harmonic generation in prism or grating co...

Micro/nano optical materials and devices are the key to many fields such as communication, sensing, biophotonics, laser, quantum optics. At present, design of micro/nano optics mainly relies on numerical methods Finite-difference time-domain (FDTD), Finite element method (FEM) difference (FDM). These bottleneck current because their dependence computational resources, low innovation efficiency,...