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...

AbstructIntermodulation and harmonic distortion are calculated for a simple fiber-optic link with a representative set of link parameters and a variety of electrooptic modulators: simple Mach-Zehnder, linearized dual and triple Mach-Zehnder, simple directional coupler (two operating points), and linearized directional coupler with one and two dc electrodes. The resulting dynamic ranges, gains, ...

This paper introduces a new concept by which it is possible to design and implement arithmetic processors using permutation networks. To demonstrate this concept, several optoelectronic arithmetic units combining optical directional coupler switches and cyclic permutation networks are designed. The designs show that addition, subtraction, and multiplication can all be performed in O(log n) time...

We present the design of a short broadband fiber directional coupler for terahertz (THz) radiation and demonstrate a 3 dB coupler with a bandwidth of 0.6 THz centered at 1.4 THz. The broadband coupling is achieved by mechanically downdoping the cores of a dual-core photonic crystal fiber by microstructuring the cores. This is equivalent to chemical downdoping but is easier to realize experiment...

We have demonstrated a polymeric electro-optic modulator based on a 132 Y-fed directional waveguide coupler. The symmetric geometry of the 132 Y-fed directional coupler provided the modulator unique characteristics of intrinsic 3 dB operating point and two complementary output ends. A low switching voltage of 3.6 V and a high extinction ratio of 26 dB were obtained with the modulator operating ...

We theoretically investigate the switching properties of nonlinear electron-wave directional couplers by applying the coupled mode theory. Analytical results for the probability of finding the electron wave in each waveguide, for arbitrary initial occupation of each waveguide, are presented. Our findings reveal that several technologically important cases can be achieved, such as significant or...