Research on application of MOOC in optical packet switching

An experiment on receiving and identifying multiple optical orthogonal codes （MOOC） sequence-based optical labels in an optical packet switching （OPS） network is reported. Two groups of MOOC with a code length of 23 and a code weight of 3 are used to identify the optical labels. The scheme and principle of OPS networks based on MOOC sequence-based optical labels are presented. Because optical labels contain OPS and routing information, the importance of optical label processing with multiple inconsecutive, random, and burst optical labels in an OPS network is pointed out. Considering the MOOC-based optical labels, we design a circuit consisting of a broadened network and a cascaded amplifier to receive multiple groups of low-power narrow pulses （optical labels in the MOOC-OPS network） with a period of 2 ns. The successful experimental results demonstrate that the designed scheme is feasible.     

Numerical simulations of the impact of wavefront phase distortions of pump on the beam quality of OPA

<正>A numerical model of optical parametric amplification(OPA) is introduced to investigate the impact of wavefront phase distortion of pump on the beam quality of signal.Numerical results show that the unidentical walk-off directions of the pump and the idler waves are the main factors leading to the transfer of wavefront phase distortions of the pump to the signal,and by reducing the angle between the two directions,the beam quality factor(M~2) can be greatly decreased and hence the good beam quality of the signal can be maintained.     

Vortex structure in superconducting iron pnictide single crystals

The vortex structure in the iron pnictide single crystals Ba_1?x K _x Fe₂As₂ and Sr_1?x K _x Fe₂As₂ of the 122 type and SmFeAsO_1?x F _x of the 1111 type has been investigated using the decoration method. In all of the crystals under investigation, no regular vortex lattice has been revealed in the magnetic field range up to 200 Oe. The disordered vortex structure is discussed in view of the vortex pinning in single crystals.     

Crossover from a continuum study of chiral susceptibility

We derive a model-independent integral formula for chiral susceptibility and attempt to present a continuum model study of it within the framework of Dyson–Schwinger equations. An appropriate regularization is implemented to remove the temperature-independent quadratic divergence inherent in this quantity. While it demonstrates a second-order phase transition characteristic in the chiral limit, the result obtained supports a crossover at physical current quark masses, which is in good agreement with recent lattice studies.     

Multiparty quantum secret sharing based on Bell measurement

A multiparty quantum secret sharing scheme based on Bell measurement is proposed and analyzed. In this scheme, all agents are not required to prepare entangled states or perform any local unitary operation. The security of the protocol is also analyzed. It is shown that any eavesdropper will introduce errors invariably and be detected if he tries to steal information about Trent’s secret. Moreover, because no classical bit needs to be transmitted except those for detection, the total efficiency of the scheme approaches to 100%.     

Analysis of a 1×32 polymer microring resonant wavelength de-multi/multiplexer assistant with interleave filter

A new 1×32 wavelength de-multi/multiplexer utilizing the microring resonator and interleave filter is proposed in this paper. A novel formula of transfer functions is presented, the parameters of microring are optimized, and the transmission characteristics of the system are analyzed. The channel spacing of the presented device is 0.4 nm. The analytical result shows that the crosstalk between adjacent channels can be reduced greatly and the filter response of the device can be improved by using the interleave filter. A bandwidth (3 dB) of 0.21 nm, an insertion loss less than 1.1 dB, and crosstalk below −32 dB were obtained for the optimized device. A method for compensating the manufacturing tolerances is discussed.     

Investigation on optimization design of equivalent water depth truncated mooring system

The oil industry is now increasingly concentrating their efforts and activities in connection with developing fields in deeper waters, ranging typically from 500 m to 3000 m worldwide. However, the modeling of a full-depth system has become difficult presently; no tank facility is sufficiently large to perform the testing of a complete FPS with compliant mooring in 1000 m to 3000 m depth, within reasonable limits of model scale. Until recently, the most feasible procedure to meet this challenge seems to be the so-called “hybrid model testing technique”. To implement this technique, the first and important step is to design the equivalent water depth truncated mooring system. In this work, the optimization design of the equivalent water depth truncated mooring system in hybrid model testing for deep sea platforms is investigated. During the research, the similarity of static characteristics between the truncated and full depth system is mainly considered. The optimization mathematical model for the equivalent water depth truncated system design is set up by using the similarity in numerical value of the static characteristics between the truncated system and the full depth one as the objective function. The dynamic characteristic difference between the truncated and full depth mooring system can be minished by selecting proper design rule. To calculate the static characteristics of the mooring system, the fourth order Runge-Kutta method is used to solve the static equilibrium equation of the single mooring line. After the static characteristic of the single mooring line is calculated, the static characteristic of the whole mooring system is calculated with Lagrange numerical interpolation method. The mooring line material database is established and the standard material name and the diameter of the mooring line are selected as the primary key. The improved simulated annealing algorithm for continual & discrete variables and the improved complex algorithm for discrete variables are employed to perform the optimization calculation. The C++ programming language is used to develop the computer program according to the object-oriented programming idea. To perform the optimization calculation with the two algorithms mentioned above respectively and the better result is selected as the final one. To examine the developed program, an example of equivalent water depth truncated mooring system optimum design calculation on a 100,000-t, turret mooring FPSO in water depth of 320 m are performed to obtain the conformation parameters of the truncated mooring system, in which the truncated water depth is 160 m. The model test under some typical environment conditions are performed for both the truncated and the full depth system with model scale factor λ=80. After comparing the corresponding results from the test of the truncated system with those from the full depth system test, it’s found that the truncated mooring system design in this work is successful. Supported by the National Natural Science Foundation of China (Grant Nos. 10602055 and 40776007) and the Natural Science Foundation of China Jiliang University (Grant No. XZ0501)     

Temperature dependent conductive behavior of pentacene in organic field-effect transistor

Impedance characterization at different temperature has been used to investigate the conductive behavior of pentacene as the semiconductor layer in organic field-effect transistor. It has been found that the pentacene exhibits an enhancement in conductivity by heating following an Arrhenius law with an activation energy transition from 0.004 to 0.018 eV at 323 K, which originates from band tail hopping that occurs around the Fermi edge.     

Direct measurement of the surface dynamics of supercooled liquid-glycerol by optical scanning a film

The surface dynamics of supercooled liquid-glycerol is studied by scanning the thickness of the glycerol film with single photon detection. Measurements are performed at room temperature well above the glycerol's glass transition temperature. It is shown that the surface dynamics of the glycerol film is very sensitive to the temperature. The linear relationship between the thickness of the film and the viscosity predicted by the Vogel--Fulcher--Tammann--Hesse (VFTH) law is also presented experimentally.     

Facile method for CLSM imaging unfunctionalized Au nanoparticles through fluorescent channels

The microscopic visualization of metal nanoparticles has become a useful tool for the investigation of their applications in cell labeling and the study of their bio-effects. In the current study, we have developed a facile method with confocal laser scanning microscope (CLSM) to observe unfunctionalized Au nanoparticles through fluorescent channels. The sharp reflected signal and photostable property of the metal nanoparticles makes the present method very ideal for fluorescent co-localization, real-time imaging, and further quantitative analysis. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users. Lan Yuan and Wei Wei contributed equally to this study.