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According to the semi-classical theory of light-matter interaction,the Bloch equations with chirped terms were established in a dense two-level medium,and an accurate and efficient fourth-order Runge-Kutta method was applied for solving the equations.After numerical simulation,the interactions between a chirped ultra-short pulse and dense resonant two-level medium were investigated,and the influences of local-field effects and chirp on Bloch vectors were gained.The numerical results show that,the evolutions of Bloch vectors and the final state of inversion are strongly modulated by the local-field effects correction coefficient and chirp parameter,which provides a method to achieve stable population inversion of control by adjusting the linear chirp parameter and local-field correction coefficient.

Twelve microsatellite loci were used to investigate genetic diversity and population structure of common carp,Cyprinus carpio from Yuan River(the upper reaches of Red River in Yunnan Province,China).One hundred and ninety two samples of adult common carp were collected in 2011 from five sampling points.A total of 201 alleles were detected over all loci and the number of alleles per locus ranged from 2 to 27.There were 113 low frequencies alleles at the frequencies less than 0.05.Mean number of alleles(NA) ranged from 12.25 to 14.67 per locus per population,effective number of alleles(NE) ranged from 8.28 to 9.73,mean observed heterozygosity(HO) and mean expected heterozygosity(HE) at the 12 loci ranged from 0.7765 to 0.8037,and from 0.7761 to 0.8080,and mean polymorphism information content(PIC) ranged from 0.7534 to 0.7843.Mean number of alleles(NA),mean effective number(NE) of alleles,mean observed heterozygosity(HO),mean expected heterozygosity(HE) and mean polymorphism information content(PIC) were 16.50,11.26,0.7927,0.8049,0.7966 respectively for overall samples.The result indicated that the genetic diversity of common carp from Yuan River was abundant.An analysis on the distribution of genetic variation(AMOVA) indicated that the variation within population was very high(95.87%),while among populations was low(1.69%).The value of fixation index and gene flow were 0.0256,9.5003 respectively for overall samples.Nei′s unbiased measures of genetic identity and genetic distance among populations rang from 0.8632 to 0.9700,0.0305 to 0.1471 respectively.This suggests that there were high genetic similarity among the 5 populations and significant genetic differentiations among the common carp individuals from Yuan River.So,the common carp from Yuan River should be managed by a population management unit.The genetic background of artificial stocking of carp larvae should not only be taken into consideration in fisheries enhancement,but also a system of evaluating the stock enhancement effectiveness should be established to prevent losing genetic biodiversity.

A novel ancillary ligand(2-(1-hydroxy-naphthyl)-benzothiozolato)(HNBT) and the corresponding red emitting phosphorescent iridium(Ⅲ) complex,Ir(ppy)2(NBT) with 2-phenylphridine(ppy) as first ligand are designed and synthesized.Saturated red-emitting electrophosphorescent devices using Ir(ppy)2(NBT) as emission center are fabricated.The thermal,photophysical,and electroluminescent properties of Ir(ppy)2(NBT) are investigated in detail.It is noteworthy that the emission spectrum shape of complex Ir(ppy)2(NBT) is similar to Gauss,which has only one emission peak centralized 614 nm with a full-width at half-maximum of 65 nm.The optimized device exhibits a maximum brightness of 6 400 cd/m2 and the peak current efficiency is 4.53 cd/A.

A scheme was proposed to construct bilinear and quadratic Hamiltonians for frequency up-and down-conversions in cavity quantum electrodynamics(QED).Generally,in nonlinear optics,the interaction that the energe swaps between different optic modes without atomic transition is named frequency conversion.The proposed scheme was based on the interactions of a single four-level atom simultaneously with two classical driving fields and a two-mode cavity field,which is in the domain of four-wave mixing.By initially preparing the atom in a suitable state,each pump light was resonant with its transition,and two quantum modes were large tune to the other two transition,respectively,In the strong laser regime,the atomic degrees of freedom could be decoupled from the cavity degrees of freedom and the frequency conversion could be realized for the cavity modes.Due to the different initial states and interactions between optic fields and atom,frequency up-and down-conversions arose,respectively.After the preparation of squeezed operation respect to Frequency down-conversion,a discussion on the feasibility of experiment was given and the theoretical value was obtained.The advantage of this proposal is to realize the transition using two cascade photons,which is dipole-forbidden in a cascade structure atom,with high efficiency.The proposal will be useful for optical quantum control and fundamental tests of quantum theory.

A triplexer was fabricated based on asymmetric Y branch waveguides Cascade Multimode interference(MMI) for fiber to the home(FTTH).The simulation results of spectral response show that output optical fields are clearly.And the demultiplexing function for download 1 490 nm and 1 550 nm and multiplexing function for upload 1 310 nm were achieved.The simulation results of finited different beam propagation method(FD-BPM) show that insertion loss is less than 1.49 dB;the bandwidths of three response wavelengths meet the demand of ITU.984 completely;the isolation for 1 310 nm is more than 47 dB;the isolation for between 1 490 nm and 1 550 nm is more than 29 dB.

A channel thermal impedance model for amorphous silicon thin film transistor is derived from a system of coupled energy equation,heat flowing equation and boundary conditions.By the use of this model,the average temperature in the active region can be calculated.Then,by considering of the effects of field oxide and interconnects between devices,a two dimensional thermal model is developed.By the use of this model,the temperature distribution in the channel can be described and the maximum junction temperature can be calculated.The accuracy of the proposed model has been verified with the device simulation data.

The polarization states of the diffraction beams of nearly perfect conducting blazed gratings in Littrow mounting are studied by numerical simulation.A FDTD program is written,the electromagnetic fields for various polarized incident beams are calculated,and the polarization states of the diffractive waves are extracted.The relation between the polarization state of the diffraction wave and the grating balzed angle and polarization angle for the linearly polarized incident wave is analyzed.In the spectral range of 1 530 ~ 1 570 nm,the polarization dispersion is studied for the linearly and circularly polarized incident beam.The most important conclusions may be significative for the engineering design.