This system uses SOI optical waveguide ring resonator chip. By using the method of selecting single direction light path, we got the resonance curve and backscattering curve of the resonant, while the system is working under different light powers. The changing rules of FWHM and resonant depth under different light powers is analyzed. And the action mechanism of optical power on the cavity resonance curve and backscattering is analyzed. Finally, the optimal working optical power of SOI integrated optical gyroscope system is determined.
Based on the asymmetric directional coupler, a polarization beam splitter based on silicon on Insulator (SOI) platform is designed for the wavelength range of 1500nm-1600nm in optical communication in this letter. The asymmetric directional coupler is composed of a regular strip shape waveguide and a sub-wavelength grating waveguide. The influence of the grating period, grating depth, and duty cycle on its polarization characteristics is analyzed. The simulation results show that the polarization extinction ratio (PER) of TE polarization is 20-23 dB and the insertion loss (IL) is 0.01-0.04dB, in the wavelength range of 1500–1600nm, while the PER of TM polarization is 15-26 dB and the IL is 0.3-0.6dB. Especially, the PER and IL are 21 dB (26 dB) and 0.31 dB (0.26 dB) for TE (TM) at the wavelength of 1550 nm. Moreover, the minimum feature size of this device is 25 μm2 . It can be effectively used in semiconductor photoelectronic devices.
A novel ultralow loss bent waveguide for single-mode operation was designed based on the Euler spiral. The proposed 180° bend (U-bend) was composed of two identical 90° Euler bends with gradient width from 1.6μm to 0.45μm and a 0.45μm wide, 2μm long strip waveguide. The proposed U-bend had ultralow losses (<−0.0005dB) and very low mode excitation ratios (MERs) of high-order modes (<−35dB) over a broad wavelength-band by lumerical simulation software. The effective radius Reff of the designed U-bend was as small as 42.547μm and the transmission ratio of fundamental-mode was 0.99988 that almost equal to 1. After simulation and computation, only the fundamental-mode could be retained and propagated in the designed U-bend waveguide with ultralow loss.
Taper is a basic device widely used in photonics technology which transmits light between the waveguides with different widths. Tapers are usually designed to be trapezoidal in shape, which is simple but has many limits. If the taper is designed to be too short, the broken lines at the junction positions between the strip waveguides (SWGs) and the taper will excite high-order modes and cause high fundamental mode loss. As a result, the traditional tapers are always with a long length which limits the miniaturization of photonic systems. To solve this problem, we proposed a method based on forth-order Bezier curve that made the taper has both small size and good performances on the transmission loss of fundamental mode and the mode excitation ratios (MERs) of high-order modes. According to the obtained results, the proposed Bezier curve method decreased the length of a taper from 100μm to 30μm on the premise of maintaining the performances.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.