Simiao Xiao

Slot-based athermal silicon arrayed-waveguide grating (AWG)

A slot waveguide structure is used in the part of arrayed waveguides in AWG instead of silicon waveguides. It is filled with high negative thermo-optic coefficient polymer in the narrow slot. The arrayed slot structure can remarkably reduce the center wavelength shift when the temperature changes. In this study, we use the polymer WIR30-490 and ZP49 to be filled in the slot. The thermo-optic coefficients of WIR30-490 and ZP49 are negative, and have the same order of magnitude with silicon. In our simulations, by adjusting several variables of the slot structure, such as the width of the slot between the pair of silicon wires, the width of the silicon waveguide, and the height of the silicon waveguide, we can get the athermal condition of AWG for each polymer. Even if there is an acceptable error on fabrication, temperature-dependent center wavelength shift of AWG can still be reduced down to 1 pm/°C. It makes the fabrication of athermal silicon AWG possible.

Photonic Properties of Silicon-on-Glass Nano-Films and its Fabrication

The photonic properties of the silicon-on-glass (SOG) nano-films are analyzed first and the reason why SOG nano-films are required for the nanophotonics is pointed. Then the method to fabricate silicon-on-glass nano-film materials for the applications of nano photonics is established. Anodic boning and selective etching are employed. SOG-based nano-films are then studied.

Turning-Mirror-Integrated Arrayed-Waveguide Gratings on Silicon-on-Insulator

In this paper, optical demultiplexers (Demuxs) with the employment of the turning-mirror-integrated (TMI) arrayed-waveguide grating (AWG) are designed and fabricated on silicon-on-insulator (SOI) materials. The waveguide array in the conventional AWG configuration is replaced by a TMI waveguide array. The devices are more compact, while the performance is comparable to that of a conventional AWG fabricated on the same wafer. The adjacent and nonadjacent crosstalks are lower than -19 and -23 dB, respectively, and the typical on-chip loss is less than 8.8 dB. The polarization-dependent wavelength shifts are between 0.048 and 0.068 nm

Fabrication of silicon-on-glass waveguides

The method to fabricate silicon-on-glass materials for the applications of integrated optics and photonics is proposed. Anodic boning and selective etching are employed. SOG-based rib waveguides and nano-films are then studied.

Improved Mach-Zehnder interferometer with micro-ring-resonator-based two-beam interferometer

An optical switch based on the Mach-Zehnder interferometer (MZI) with a micro-ring resonator as the twobeam interferometer is proposed. By configuring appropriate coupling ratios, the improved MZI can always obtain a low crosstalk, even with seriously unbalanced interferencing beams.

Silicon-based digital optical switch with slot structure

In this paper a silicon-based digital optical switch (DOS) with the slot structure is demonstrated. By filling electro-optic polymer in the void slot of the branches, the electro-optic effect can be applied to the DOS, and a high-speed silicon switch with digital switching property can be achieved. Analysis shows that the crosstalk is about 35dB, switching speed is less than 1ps, and the device length is less than 1mm.

Ring-resonator-assisted optical switch with high extinction ratio

This paper presents a novel micro-ring-resonator-assisted structure as an optical switch. This device couples two outputs of a 1x2 power splitter into a micro-ring resonator (MRR). The double-beam interference will occur in the MRR. If the phase difference between the beams and the coupling coefficients of MRR are set properly, the device can switch the light by applying phase shift on MRR. High extinction ratio or low crosstalk can be achieved, even if the modulation additional loss is large.

Electro-optic silicon modulator with horizontal photonic crystal slot slab

The properties of truly confined modes of a 2D hex horizontal photonic crystal slot slab waveguide are analyzed. Then the dispersion of liner defect waveguide is calculated. In addition, what influence the slots with different height have over the band structure and the group velocity dispersion of the defect mode waveguide are analyzed. Based on these studies, an ultra-compact silicon-based Mach-Zehnder amplitude modulator is proposed. For a design with almost negligible first order chromatic dispersion in an optical bandwidth of 1THz, we predict a modulation bandwidth of 40GHz and a length of about 80µm. This is achieved by infiltrating an electro-optic polymer into a slotted photonic crystal waveguide, the strong field confinement in slotted waveguides and the slow light interaction enhancements provided by the photonic crystal waveguide, where group velocity and dispersion may be controlled.