Parabolic tapered photonic crystal cavity in silicon

We demonstrate the design, fabrication, transmission and nearfield characterization of a novel parabolic tapered 1D photonic crystal cavity in silicon. The design allows repeatable device fabrication, high quality factor and small modal volume. © OSA 2012.

Parabolic tapered photonic crystal cavity in silicon

We demonstrate the design, fabrication, transmission and nearfield characterization of a novel parabolic tapered 1D photonic crystal cavity in silicon. The design allows repeatable device fabrication, high quality factor and small modal volume. © 2012 OSA.

Parabolic tapered photonic crystal cavity in silicon

We demonstrate the design, fabrication, transmission spectrum measurement, and near-field characterization of a parabolic tapered one-dimensional photonic crystal cavity in silicon. The results shows a relatively high quality factor (∼43 000), together with a small modal volume of ∼ 1. 1 (λ/n) 3. Moreover, the design allows repeatable device fabrication, as evident by the similar characteristics obtained for several tens of devices that were fabricated and tested. These demonstrated 1D PhC cavities may be used as a building block in integrated photonic circuits for optical on-chip interconnects and sensing applications. © 2012 American Institute of Physics.

Parabolic tapered photonic crystal cavity in silicon

We demonstrate the design, fabrication, transmission and nearfield characterization of a novel parabolic tapered 1D photonic crystal cavity in silicon. The design allows repeatable device fabrication, high quality factor and small modal volume. © OSA 2012.

Assembly and inspection of liquid crystal on silicon devices

Liquid crystal on silicon (LCOS) is one of the most exciting technologies, combining the optical modulation characteristics of liquid crystals with the power and compactness of a silicon backplane. The objective of our work is to improve cell assembly and inspection methods by introducing new equipment for automated assembly and by using an optical inspection microscope. A Suss-MicroTec Universal device bonder is used for precision assembly and device packaging and an Olympus BX51 high resolution microscope is employed for device inspection. © 2009 Optical Society of America.

Flexible Control of Light Propagation Using a Novel Photonic Crystal Hetero-Waveguide Based on Silicon-on-Insulator Slab

We demonstrate a photonic crystal hetero-waveguide based on silicon-on-insulator (SOI) slab, consisting of two serially connected width-reduced photonic crystal waveguides with different radii of the air holes adjacent to the waveguide. We show theoretically that the transmission window of the structure corresponds to the transmission range common to both waveguides and it is in inverse proportion to the discrepancy between the two waveguides. Also the group velocity of guided mode can be changed from low to high or high to low, depending on which port of the structure the signal is input from just in the same device, and the variation is proportional to the discrepancy between the two waveguides. Using this novel structure, we realize flexible control of transmission window and group velocity of guided mode simultaneously.

A ministop band in a single-defect photonic crystal waveguide based on silicon on insulator

This paper reports that a two-dimensional single-defect photonic crystal waveguide in the F-K direction with triangular lattice on a silicon-on-insulator substrate is fabricated by the combination of electron beam lithography and inductively coupled plasma etching. A ministop band (MSB) is observed by the measurement of transmission characteristics. It results from the coupling between the two modes with the same symmetry, which is analysed from the stimulated band diagram by the effective index and the two-dimensional plane wave expansion methods. The parameter working on the MSB is the ratio of the radius of air holes to the lattice constant, r/a. It is obtained that the critical r/a value determining the occurrence or disappearance of MSB is 0.36. When r/a is larger than or equal to 0.36, the MSB occurs. However, when r/a is smaller than 0.36, the MSB disappears.

Design and Fabrication of a Photonic Crystal Channel Drop Filter Based on an Asymmetric Silicon-on-Insulator Slab

We report on the design and fabrication of a photonic crystal (PC) channel drop filter based on an asymmetric silicon-on-insulator (SOI) slab. The filter is composed of two symmetric stick-shape micro-cavities between two single-line-defect (W1) waveguides in a triangular lattice, and the phase matching condition for the filter to improve the drop efficiency is satisfied by modifying the positions and radii of the air holes around the micro-cavities. A sample is then fabricated by using electron beam lithography (EBL) and inductively coupled plasma (ICP) etching processes. The measured 0 factor of the filter is about 1140, and the drop efficiency is estimated to be 73% +/- 5% by fitting the transmission spectrum.

A photonic crystal waveguide with silicon on insulator in the near-infrared band

A two-dimensional (2D) photonic crystal waveguide in the Gamma-K direction with triangular lattice on a silicon-on insulator (SOI) substrate in the near-infrared band is fabricated by the combination of electron beam lithography and inductively coupled plasma etching. Its transmission characteristics are analysed from the stimulated band diagram by the effective index and the 2D plane wave expansion (PWE) methods. In the experiment, the transmission band edge in a longer wavelength of the photonic crystal waveguide is about 1590 nm, which is in good qualitative agreement with the simulated value. However, there is a disagreement between the experimental and the simulated results when the wavelength ranges from 1607 to 1630 nm, which can be considered as due to the unpolarized source used in the transmission measurement.

Structure tuning of line-defect waveguides based on silicon-on-insulator photonic crystal slabs

We present fabrication and experimental measurement of a series of photonic crystal waveguides. The complete devices consist of an injector taper down from 3 mu m into a triangular-lattice air-hole single-line-defect waveguide with lattice constant from 410nm to 470nm and normalized radius 0.31. We fabricate these devices on a siliconon-insulator substrate and characterize them using a tunable laser source over a wavelength range from 1510nm to 1640nm. A sharp attenuation at photonic crystal waveguide mode edge is observed for most structures. The edge of guided band is shifted about 30nm with the 10nm increase of the lattice constant. We obtain high-efficiency light propagation and broad flat spectrum response of the photonic crystal waveguides.

Structure dependence of mode edges in photonic crystal waveguide with silicon on insulator

The mode edges of photonic crystal waveguide with triangular lattice based on a silicon-on-insulator slab are investigated by combination of the effective index method and two-dimensional plane wave expansion method. The variations of waveguide-mode edges with structure parameters of photonic crystal are deduced. When the ratio of the radius of air holes to the lattice constrant, r/Lambda, is fixed and the lattice constant of photonic crystal, Lambda, increases, the waveguide-mode edges shift to longer wavelengths. When Lambda is fixed and r/Lambda increases, the waveguide-mode edges shift to shorter wavelengths. Additionally, when r/Lambda and Lambda are both fixed, the radius of the two-row air holes adjacent to the waveguide increases, the waveguide-mode edges shift to shorter wavelengths.

A two-dimensional photonic crystal slab mirror with silicon on insulator for wavelength 1.3 mu m

A concrete two-dimensional photonic crystal slab with triangular lattice used as a mirror for the light at wavelength 1.3 mu m with a silicon-on-insulator (Sol) substrate is designed by the three-dimensional plane wave expansion method. For TE-like modes, the bandgap in the F-K direction is from 1087nm to 1559nm. The central wavelength in the bandgap is about 1.3 mu m, hence the incident light at wavelength 1.3 mu m will be strongly reflected. Experimentally, such a photonic crystal slab is fabricated on an SOI substrate by the combination of EBL and ICP etching. The measurement of its transmission characteristics shows the bandgap edge in a longer wavelength is about 1540mn. The little discrepancy between the experimental data and the theoretical values is mainly due to the size discrepancy of the fabricated air holes.

Effects and numerical analysis of argon gas flow on the oxygen concentration in Czochralski silicon single crystal growth

Argon gas, as a protective environment and carrier of latent heat, has an important effect on the temperature distribution in crystals and melts. Numeric simulation is a potent tool for solving engineering problems. In this paper, the relationship between argon gas flow and oxygen concentration in silicon crystals was studied systematically. A flowing stream of argon gas is described by numeric simulation for the first time. Therefore, the results of experiments can be explained, and the optimum argon flow with the lowest oxygen concentration can be achieved. (C) 2002 Elsevier Science B.V. All rights reserved.

Design and Fabrication of a Photonic Crystal Channel Drop Filter Based on an Asymmetric Silicon-on-Insulator Slab

We report on the design and fabrication of a photonic crystal (PC) channel drop filter based on an asymmetric silicon-on-insulator (SOI) slab. The filter is composed of two symmetric stick-shape micro-cavities between two single-line-defect (W1) waveguides in a triangular lattice, and the phase matching condition for the filter to improve the drop efficiency is satisfied by modifying the positions and radii of the air holes around the micro-cavities. A sample is then fabricated by using electron beam lithography (EBL) and inductively coupled plasma (ICP) etching processes. The measured 0 factor of the filter is about 1140, and the drop efficiency is estimated to be 73% +/- 5% by fitting the transmission spectrum.

Theoretical and Experimental Studies of an Ultra-compact Photonic Crystal Corner Mirror Based on Silicon-On-Insulator

An ultra-compact silicon-on-insulator based photonic crystal corner mirror is designed and optimized. A sample is then successfully fabricated with extra losses 1.1 +/- 0.4dB for transverse-electronic (M) polarization for wavelength range of 1510-1630nm.