Zhen

Crystal structure and near-infrared luminescence properties of novel binuclear erbium and erbium–ytterbium cocrystalline complexes

Three binuclear complexes of erbium and ytterbium, Er2(Ba)6(Phen)2, Yb2(Ba)6(Phen)2 and Er1.4Yb0.6(Ba)6(Phen)2 (Ba = benzoate, Phen = 1,10-phenanthroline), were synthesized and structurally characterized, and their luminescent properties examined in detail. Compared with the binuclear complex Er2(Ba)6(Phen)2, the NIR luminescence of the erbium ion in Er1.4Yb0.6(Ba)6(Phen)2 is enhanced because of the coexistence of the ytterbium ion through an ytterbium-to-erbium energy transfer process. The full width at half maximum, centered at 1535 nm in the emission spectrum of Er1.4Yb0.6(Ba)6(Phen)2, is 108 nm, excited at 975 nm, which has potential to enable a wide-gain bandwidth for optical amplification. The X-ray single crystal structure confirms that this is an excellent binuclear complex model with a short metal-to-metal distance (about 4 A) to facilitate the intramolecular (not intermolecular) Yb–Er energy transfer process. ESI-MS confirmed the molecules Er2(Ba)6(Phen)2, Yb2(Ba)6(Phen)2 and ErYb(Ba)6(Phen)2 exist in solution.

Study of an Electro-Optic Polymer Modulator

In order to characterize electro-optic polymer modulators, a full-vectorial finite-difference mode solver has been developed to solve Maxwells equation for an optical waveguide, and a finite-element method has been employed to analyze a microwave electrode. A systematic and detailed discussion has been presented to describe and design a modulator about performance parameters: <formula formulatype=inline><tex Notation=TeX>

Improved coupling technique of ultracompact ring resonators in silicon-on-insulator technology

V_{pi}L,Delta fL, N_{m}, alpha_{c}

The Basic Building Block of

</tex></formula>, and <formula formulatype=inline> <tex Notation=TeX>

{\lambda}

z_{c}

-Router With Multimode-Interference Waveguide Crossings on Silicon-on-Insulator Technology

</tex></formula> with all the necessary design parameters: optical waveguide (width and height), electrode (width and height), and thickness of cladding layer. We can see that most of the results are interesting, even very different from general opinions, for example, one can observe that <formula formulatype=inline><tex Notation=TeX>

Dependence of integrated acousto-optical devices with one and two modulated arms on the static phase difference

V_{pi}L

Numerical model of the polymer electro-optic waveguide

</tex></formula> is not always reduced with an increased width of optical waveguide. These will be helpful for an optimized design of a modulator.

A novel concept of acousto-optic ring frequency shifters on silicon-on-insulator technology

In order to improve the coupling coefficient between a bus waveguide and a bent waveguide of an ultracompact microring to obtain the critical coupling, a design using a bent bus waveguide with reduced width is provided to maintain a better phase matching and increase the coupling. A full vectorial finite difference model, specifically suited for high index contrast and smaller size waveguides, for example, a waveguide in the silicon-on-insulator (SOI) technology, is developed. As a validation, the straight and bent waveguides are simulated using this model, whose results are compared with the results deduced from the measurement results of the ultracompact ring resonators in SOI technology. Also, the model solver is performed to simulate the design, and an experiment is implemented to testify the design.

The optimum design model of two resonators system

Optical properties of the λ-router basic building block are simulated using a matrix method. Experiments are performed for the -router basic building block with multimode-interference (MMI) crossings, which shows large free spectral range (~35 nm) and more than 24 dB on/off contrast of the drop resonance. Theoretical and experimental results reveal that the λ-router basic building block with MMI crossings can suppress the crosstalk (defined as the difference between the drop efficiency and the throughput attenuation at resonance), offer relatively symmetric resonance, and increase the on/off contrast of the drop resonance, compared with a λ-router building block using conventional crossings.