We have investigated the Bragg gratings for surface plasmonic polaritons modes in the metal-dielectric-air waveguide and proposed a bidirectional coupler which is capable to guide the incident light at different wavelengths along two predetermined directions.
We introduce a simple procedure for high-Q cavity design in photonic crystal heterostructures. The key parameter in the optimization process is the relative position of the resonant frequency within the mode-gap.
We report on the study of incorporation of organic thin film semiconductors with GaN to explore new types of photodetector or solar cell application. Photovoltaic effect and photoconductivity gain have been demonstrated using GaN/CuPc and GaN/alpha -NPD hybrid device structure, which offer new opportunities in design of versatile optoelectronic devices.
We propose a design method for a tunable time-delay element based on the eye-diagram metrics of a system. Two approaches using dispersion management are given, and both show improved fractional delay with high data fidelity.
Operation of terahertz quantum cascade lasers have now been demonstrated between 1.2 and 4.9 THz. Extremely narrow linewidths and continuous tunability have been reported, with applications in imaging, radio-astronomy and process control.
We present an all-fiberreg pump combiner with 32 ports. This device is designed to provide high isolation providing intrinsic pump protection. We demonstrated that over 200 W of pump power can be deliver in 20/400 mum fiber.
Polymer lenses were fabricated using a fluid-filled tunable molding process providing a simple and cost-effective way to control lens curvature and shape. This approach enables fast prototyping and shortens the design cycle for optical systems.
Fourier operator is used in the vectorial Helmholtzpsilas equation for the calculation of layer modes in a 2D slice of a photonic device. The slice modes are then propagated throughout the device via scattering matrices.
The development of integrated polarization manipulating devices opens the perspective on the use of polarization as a new design dimension in InP-based integrated optics. Examples will be given of how this results in additional functionalities.
We designed and fabricated simple-structure HAFs having lambda0 in a 1.0 mum band as well as low confinement loss and single mode operation over wide range of wavelengths. The developed HAFs showed high non-linearity and good connectivity.
We design, fabricate and demonstrate a hybrid nanocrystal/patterned p-i-n device that utilises fluorescence energy transfer and exhibits a three-fold increase of the measured photocurrent compared to its bare p-i-n counterpart.
We show cascaded silicon microring resonators with 1.5-mum radius critically coupled to a narrower waveguide. A coupled Q of 9,000 is achieved. Devices are fabricated with the widely-available SEM-based lithography system using a stitching-free design.
The novel filtering scheme proposed here allows for implementation of arbitrary spectral transfer functions. It is demonstrated on design and realization of a filter for transform-limited 1.6-ps flat-top pulse synthesis.
Active control over the resonant frequency of a surface plasmon excitation is demonstrated. Tunable semiconductor-based extraordinary optical transmission gratings were fabricated, designed for transmission between 7 and 10 mum, showing a tuning range of over 25 cm-1.
Two novel designs for optical cloaking based on nonlinear transformations for TM and TE polarizations are presented. This critical development builds upon our previous work on nonmagnetic cloak designs and high-order transformations.
Precise semiconductor saturable absorber mirrors (SESAM) design has enabled modelocked lasers with >100 GHz pulse repetition rate or >10 muJ pulse energy. We discuss a new method for wide dynamic range nonlinear reflection measurements of SESAMs with <0.05% accuracy.
We report design and results on realization of an asymmetric co-axial dual-core fiber for an inherently gain flattened EDFA with median gains ges 28 dB and gain excursion within plusmn 2 dB across the C-band.
We review all known approaches to suppress thermal effects in Faraday isolator: design with two TGG crystals, cooling to nitrogen temperature, disc geometry, non-traditional magneto-optics material, advanced permanent magnet design, and superconductive solenoid.
Financed by the National Centre for Research and Development under grant No. SP/I/1/77065/10 by the strategic scientific research and experimental development program:
SYNAT - “Interdisciplinary System for Interactive Scientific and Scientific-Technical Information”.