Photon-counting statistics-based support vector machine with multi-mode photon illumination for quantum imaging.

We propose a photon-counting-statistics-based imaging process for quantum imaging where background photon noise can be distinguished and eliminated by photon mode estimation from the multi-mode Bose-Einstein distribution. Photon-counting statistics show multi-mode behavior in a practical, low-cost single-photon-level quantum imaging system with a short coherence time and a long measurement time interval. Different mode numbers in photon-counting probability distributions from single-photon illumination and background photon noise can be classified by a machine learning technique such as a support vector machine (SVM). The proposed photon-counting statistics-based support vector machine (PSSVM) learns the difference in the photon-counting distribution of each pixel to distinguish between photons from the source and the background photon noise to improve the image quality. We demonstrated quantum imaging of a binary-image object with photon illumination from a spontaneous parametric down-conversion (SPDC) source. The experiment results show that the PSSVM applied quantum image improves a peak signal-to-noise ratio (PSNR) gain of 2.89dB and a structural similarity index measure (SSIM) gain of 27.7% compared to the conventional direct single-photon imaging.

All-optical flip-flop with high on-off contrast ratio using two injection-locked single-mode Fabry-Perot laser diodes.

An all-optical flip-flop with inverted output is presented. The flip-flop is realized based on the optical bistability of an injection-locked single-mode Fabry-Perot laser diode (FP-LD). The operation principle is explained and experimental results are presented in this paper. The flip-flop with separate optical set and reset inputs had an on-off contrast ratio of over 35 dB.

Optical burst add-drop multiplexing technique for sub-wavelength granularity in wavelength multiplexed ring networks.

We demonstrate optical burst add-drop multiplexing as a practical application of the optical burst switching technology in a wavelength-division-multiplexed ring network. To control optical bursts in the network, a burst identifier (BI) for delivering control information, and a BI processor for handling the BI, were designed. Optical bursts of 10- to 100-mus in length were optically multiplexed or demultiplexed in an intermediate node of the ring network. The demonstration shows that the optical burst add-drop multiplexing technique provides sub-wavelength granularity to a ring network.

Mutant presenilin 2 causes abnormality in the brain lipid profile in the development of Alzheimer's disease.

Mutation in the presenilin 2 (PS2mt) is known to be one of factors involved in the development of Alzheimer's disease (AD). It was recently revealed that an abnormality of lipid metabolism is a phenomenon occurring in AD. Therefore, the aim of this study was to investigate the potential relationship between the mutation of PS2 and alterations of the lipid profile within the brain. The results showed there increases in the levels of cholesterol, low density lipoprotein and triglyceride, but a decrease in the level of high density lipoprotein in brain tissues expressing mutant PS2. These findings indicated that PS2mt is involved in the abnormalities of the lipid profile, which could cause or result in the development of AD.

All-optical flip-flop based on the bistability of injection locked Fabry-Perot laser diode.

We demonstrate the operation of a novel all-optical flip-flop. The flip-flop consists of a slave Fabry-Perot laser diode (FP-LD) and a specially designed master FP-LD which has a built-in external cavity and operates in single longitudinal mode oscillation. The set and reset pulses were generated by external modulators at 1 Gbit/s. The rising and falling times of the output signal in on-off operation of the flip-flop were about 50 ps. The required powers of both set and reset pulses were less than -9 dBm.