Topic
Extinction ratio
About: Extinction ratio is a research topic. Over the lifetime, 8541 publications have been published within this topic receiving 111908 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, a novel ultra-compact photonic tuneable notch filter with large bandwidth, high extinction ratio, fast response, and flat stopband is modeled and designed, which consists of a silicon-based ring resonator with one-dimensional photonic crystal superimposed onto a ring portion.
Abstract: A novel ultra-compact photonic tuneable notch filter with large bandwidth, high extinction ratio, fast response, and flat stopband is modeled and designed. It consists of a silicon-based ring resonator with one-dimensional photonic crystal superimposed onto a ring portion. Engineering the defects into the photonic crystal section allows to achieve the equalization of the bottom band of the filter response. Large bandwidth ( B = 10.43 GHz) and high extinction ratio (ER = 41 dB) have been attained with a frequency response of the first-order Butterworth filter type. Continuous and wide range tunability of the central frequency (15 GHz) has been obtained by using the carrier injection technique, together with fast reconfigurability (a1 ns) and power consumption of 47 mW. The device footprint is as very small as about 150 μm2. This performance makes the proposed device suitable for several filtering applications, such as wireless networks (5G) and telecommunication reconfigurable payloads in Telecom and Space scenario, respectively.
35 citations
TL;DR: The authors describe a general method to extract the frequency chirping of Mach-Zehnder modulators based on direct measurements of the output spectrum and allows measurement of the intrinsic chirp parameter to an accuracy of 5%.
Abstract: The authors describe a general method to extract the frequency chirping of Mach-Zehnder modulators based on direct measurements of the output spectrum. This method is independent of the modulator extinction ratio and allows measurement of the intrinsic chirp parameter to an accuracy of 5%.
35 citations
TL;DR: In this article, the Fourier Eigenmode Expansion Method was used to reduce the length of an MMI coupler without any penalty on the device performance in the full C-band (1530 nm) and 1570 nm.
Abstract: Multimode interference couplers (MMIs) are fundamental building blocks in photonic integrated circuits. Here it is experimentally demonstrated, for the first time, a two-fold length reduction in an MMI coupler without any penalty on device performance. The design is based on a slotted 2 × 2 MMI fabricated on a commercial silicon-on-insulator (SOI) substrate. The slot is implemented with a subwavelength grating (SWG) comprising holes fully etched down to the oxide cladding, thereby allowing single etch step fabrication. The device has been designed using an in-house tool based on the Fourier Eigenmode Expansion Method. It has a footprint of only 3.5 μm x 23 μm and it exhibits a measured extinction ratio better than 15 dB within the full C-band (1530 nm‒1570 nm). SWG engineered slots thus offer excellent perspectives for the practical realization of MMIs couplers with substantially reduced footprint yet with outstanding performance.
34 citations
Patent•
06 Jul 2007TL;DR: In this article, a WDM-PON system using a conventional downstream optical signal reusing method is presented. But, there is an inventory problem that different optical transmitter types need to be provided for operation, management, replacement, etc. of a system.
Abstract: In a Wavelength-Division-Multiplexed Passive Optical Network (WDM-PON) utilizing a conventional downstream optical signal reusing method, there is an inventory problem that different optical transmitter types need to be provided for the operation, management, replacement, etc. of a system. A WDM-PON system according to the present invention, includes: a seed light (SL) unit generating a seed light whose wavelength intervals and center wavelengths are adjusted using at least one seed light source; an optical line terminal (OLT) receiving the wavelength-multiplexed seed light from the seed light unit, transmitting a downstream optical signal to a subscriber of the WDM-PON, and receiving a upstream optical signal from the subscriber; and an optical network unit (ONU) receiving the downstream optical signal from the OLT, flattening and modulating the downstream optical signal with upstream data so that the downstream optical signal is reused for carrying upstream data. It is possible to improve the quality and reliability of downstream transmission by sufficiently increasing an extinction ratio, and improve the quality and reliability of upstream transmission by sufficiently flattening an input downstream optical signal in a semiconductor optical amplifier.
34 citations
TL;DR: The proposed polarizer has an ultra-low insertion loss of less than 0.04 dB for the TE mode and is designed and experimentally demonstrated on silicon-on-insulator platform.
Abstract: We have designed and experimentally demonstrated an integrated transverse electric (TE)-pass polarizer on silicon-on-insulator platform. The polarizer consists of an asymmetric coupling section where only the transverse magnetic (TM) mode is coupled to the cross-hybrid plasmonic waveguide and attenuated. The TE mode does not couple and passes through the polarizer. The polarizer was fabricated on the silicon-on-insulator platform. The device is 30 μm long, has a high extinction ratio of more than 28 dB over 150 nm bandwidth, and has a good fabrication tolerance. Most important, the proposed polarizer has an ultra-low insertion loss of less than 0.04 dB for the TE mode.
34 citations