Newly developed hollow-core photonic crystal fibers(HC-PCFs)have increasingly aroused intense research interests because of its unique wave-guiding properties based on the photonic band gap effect. Such fibers have been considered to be very important in applications of high-power delivering and controlling,optical signal processing,and next-generation photonic devices. Recent advances in HC-PCFs are reviewed,including progresses in both fundamental characteristics of mode-guiding,loss mechanism,dispersion and nonlinearities,and applications in high-power fiber-optic delivering,controlling ultra-short optical pulses propagation with dispersion and nonlinear management,nonlinear interactions between light and matters,optical communications and novel photonic devices.

Quantum secure direct communication(QSDC)is a new type quantum communication scheme based on quantum mechanics,which can transmit deterministic information and is more close to classical communication compared with earlier quantum key distribution(QKD)schemes which require auxiliary pre-distribution of secret key,and has become an important branch of quantum communication in recent years. A comprehensive review is presented about the present development of QSDC,with typical QSDC schemes based on various quantum principles as well as the comparisons between them. Then the experimental research on QSDC is reviewed briefly and the future direction is prospected in the end.

The Lie group method is a powerful tool to study the nonlinear differentical equations. By using the classical or nonclassical Lie symmetry method we can get amount of exact solutions of the nonlinear differential equations. For the breaking soliton equation,by applying the CK method,we obtain the Backlund transformation of finding solution,so some new solutions are found. We generalize the results in the paper [4～8].

The frequency-domain optical delay line(FD-ODL)is a kind of optical scanning technology,which consists of a diffraction grating,a lens,and a scanning mirror. When employing FD-ODL in optical coherence tomography(OCT)system,the reference scanning speed at meter-per-second can be achieved to support image acquisition at video rate. An analysis about the principle of the FD-ODL is made at the point of geometry optics. The results show that the frequency of the optic length or phase variation is almost linear to the scanning angular frequency as the scan angle is very small. The image of an OCT system based on this structure proves that it can avoid blur induced by the displacement of the living tissue. In addition,a new scanning device is also proposed.

A series of new 70TeO2－(15－x)B2O3－xNb2O5－15ZnO－1 wt%Er2O3(TBN x=0,3,6,9,12,15 mol%)tellurite glasses were prepared. The thermal stability and spectral properties,such as absorption spectra and emission spectra of the glass samples were measured and investigated. Three intensity parameters Ωt(t= 2,4,6)(Ω2=(5.42～6.76)×10－20cm2,Ω4=(1.37～1.73)×10－20cm2,Ω6=(0.70～0.94)×10－20cm2)of Er3+ were calculated by Judd-Ofelt theory. It was found that the intensity parameters Ωt(t=2,4,6)increase with the increasing of Nb2O5 content from 0 mol% to 6 mol% and then decrease. It indicates that the covalence between the Er3+ and O2－ is mainly affected by the number of non-bridging oxygen ions. However,the effect of the electro negativity between negative ions and positive ions on the covalence between the Er3+ and O2－ can be neglected. The stimulated emission cross-section(σe=(0.77～0.91)×10－20cm2)of the Er3+ ions 4I13/2→4I15/2 transition were calculated according to the McCumber theory and the full width at half maximum(FWHM=65～73 nm)of the 4I13/2→4I15/2 emission were measured. The FWHM and emission cross-section of Er3+ ions in different glass hosts were compared. The results show that this tellurite glass has wider bandwidth and could be the promising host material for broadband amplification.

Based on the third-order aberration theory,a design method is put forward for beam expander that the aberration of an object lens and an eyepiece are conjugated,a beam expander with aspheric is designed and made up of two lens. The result of design shows that aberration of system is well corrected. In order to test the beam divergence angle for 1.064 μm invisible wavelength,the method is put forward for testing of beam divergence angle with linear CCD and oscillograph,this testing method is handy and easy to be realized,and testing precision is high.

For the fabrication of conicoid,it is widely used to put a knife at the anaberrational point for knife-edge test or use interferometer for interfering test. So resolving the anaberrational points of conicoid is important for testing. Based on the third-order aberration theory,the method of resolving two conjugate anaberrational points is developed. The related functions,graphs,optical layouts and tables are given,which are very helpful for the conicoid testing.

With aim to enhance the output intensity of X-ray laser(XRL)under the condition of low pump energy,theoretical analysis and numerical simulation were presented on double prepulses and also curved target techniques. The simulation results indicate there is a good pulse structure of 2 ns/5 ns(2nd prepulse dalay/main pulse delay)that can optimize the gain area of plasma. The XRL experiment of Ne like Cr(J=0-1,3p-3s transition)pumped by the double prepulse was performed on “XingGuang Ⅱ” laser,and a 28.5 nm single line XRL was achieved,as well as other significant results. The XRL output intensity shows much reliance on the last prepulse energy when the delay time is fixed. The experimental and calculation results show good consistency.

Using the AOM active mode-locked Nd∶YVO4 laser signal light system and a Yb3+-doped D-shape double-clad fiber,a fiber amplifier is setup which has a 320 MHz laser pulse output. The fiber amplifier has a 20 dB signal gain output at 1064 nm,with the average power 1.02 W. It can be used in free-space laser communication system as emission head. The experiment is composed by the high repetition frequency mode-locked laser as signal light,the Yb3+-doped fiber for amplifier,and double frequency green light. At the same time,some influence factors of self oscillation spectrum of the fiber amplifier system are investigated. At last,the experimental results are analysed and discussed,and the improving measures for the system put forward.

The influence of rf(radio frequency)frequencies on long time evolution of atomicity density of two-component Bose-Einstein condensations is studied. The results demonstrate that the atomicity density of BEC presents a quantum collapse and revival(C-R),which is typical in quantum mechanics when the rf frequency is small enough and the time is fairly long. When the rf frequencies increased and the time prolonged,the oscillation curve of C-R declines as a whole with time.

We propose a theoretical scheme for the implementation of a non-local quantum SWAP operation on two spatially separated entangled pairs by a three-qubit entangled state and a Bell state,and we show that the operation can swap two qubits of these entangled pairs. The feature of the scheme is that a third side is included,who may participate the process of quantum non-local implementation as a supervisor. Furthermore,when the quantum channel is partially entangled,the third one can rectify the state distorted by imperfect quantum channel.

The dynamical properties of light phase in the system of a cascade three-level atom interacting with a single-mode coherent state field are studied. The influence of the atomic motion,the field-mode structure,and the intensity of the atom-field coupling on the phase probability distribution and the phase diffusion are discussed. The results show that the dynamical properties of light phase are determined not only by the intensity of the atomfield coupling,also by the velocity of the atomic motion and the parameter of the field-mode structure through the time factor g■(t)=2－1gt－(4εp)－1sin(2εpgt).

Dynamics of properties of light field of non-resonance interaction between V-type three-level atom and a single mode via intensity-dependent coupling is studied by means of the quantum theory. The influences of initial average photon numbers and the detuning are discussed

“Endlessly single-mode” operation is the most remarkable characteristic of photonic crystal fibers. Birks et al. explained it reasonably by effective index model,but considerable error was engender in quantitative analysis,and the properties of photonic crystal fibers with larger filling ratio can't be analyzed by this method because of its scalar approximation. Effective index model is applied for modeling photonic crystal fibers,but improvement is made:(1)effective core radius and the normalized frequency which determines the second modal cutoff are more exact;(2)full vector method is used. The characteristic of mode cutoff of photonic crystal fibers is studied. The normalized frequency is calculated for a range of fiber parameters and wavelengths. Relative cutoff wave number for some fiber parameters is obtined,and the relative cutoff wave number and its asymptotic bound are used to determine the boundary of three operation regimes of photonic crystal fibers with endlessly single-mode,single-mode and multi-mode operation. The result obtained is in good agreement with numerical methods,and calculation is more convenient than numerical methods.

Chua's circuit,which is improved to integrate conveniently,is presented. A driveresponse chaotic synchronization system is constructed,which possesses to a certainly stability,resisting-disturbance and so on,by means of research,it can be concluded that the chaotic synchronization system is provided with the characteristic of chaos synchronization self-maintenance,and the research results are also presented. Utilizing the characteristic,the critical problem of how to simultaneously transmit the controlling signal of chaotic synchronization and the secret signal at a channel can be solved. The experiment result provides the foundation of putting chaos into practice application to secret communication.

A set of experiments designed to study the anisotropic spatial dependence of second harmonic generation(SHG)from the surface of single crystal metals were presented. The anisotropic dependence of reflected SHG from Al2O3/Al(111)interface was studied. The isotropic dependence of the SHG signal is used to probe the structural symmetry of Al2O3/Al(111)interface. The SHG probe was also used to follow pulsed laser annealing(PLA)of the Al2O3/Al(111)interface. For peak laser powers per pulse ranging from 2×106W/cm2 to 9.6x106W/cm2,the anisotropic dependence of the SHG signal was not found to vary from experiment to experiment. Using P-polarized pump laser light,the P-polarized SHG signal exhibits three equally spaced,equal intensity maxima during a single complete rotation of the Al2O3/Al(111)interface about the interface normal. When the incident P-polarized 1064 nm pump laser light possesses an incident peak power of 12×106W/cm2 per pulse,the Al2O3/Al(111)interface is damaged. After this damage is made,the interface does not exhibit a symmetrical anisotropic dependence in the SHG signal. Annealing of the interface is found to occur when the incident P-polarized 1064 nm pump laser light has an incident peak power of 11×106W/cm2 per pulse. The intensity of the P-polarized 532 nm SHG signal generated in reflection from this annealed interface exhibits a reduced anisotropic component in the SHG signal.

As a new advanced method of measuring trace gases,the technology of tunable diode laser absorption spectroscopy(TDLAS)has been applied in the fields of atmospheric chemistry and pollutant gases monitoring. When the absorption optic length can not be effective increased in the system,the noise of system will limit the capabilities of the system and should be reduced to increase the detection limit of TDLAS system. The origin of noise of TDLAS system is introduced and the second-harmonic detection of CO and CO2 with shortpath optic length at atmosphere pressure in the near-infrared wavelength also presented. The detection limit of CO is 0.73% and the one of CO2 is 0.98%. It is obvious that the TDLAS system is fit for the environmental monitor with the high detection limit.

In order to study the characteristics of cirrus,high-altitude cirrus clouds over Hefei,Anhui(31.90°N,117.16°E)were observed by L300 Mie lidar. These cirrus clouds were simultaneously detected when the lidar took regular nighttime measurements of tropospheric aerosol. The structures and optical properties of the cirrus clouds as well as their time variation are discussed and analysed. Our results show that the peak of cirrus over this area range mainly from 8 km to 11 km,and their structures change with season as well.

A method for the measurement of scattering characteristics of the sample is proposed. The powder pressboard of F4(polytetrafluoroethylene(PTFE))was used as reflection standard board. We measured the reflection luminous intensity scattering data of sample and standard board. By transmiting through reflection standard board,we obtained the sample's BRDF at hemisphere space(λ= 1.06μm). Then we compared this result with the output result. of the model. The experimental result indicates that this method is a feasible to analyse the scattering characteristics of the sample.

The leakage of natural gas is not only economic loss,also the fountain of dangerous. Optical sensors based on NIR tunable diode laser absorption spectroscopy were widely used because of high sensitivity,small volume and less maintenance. A portable remote sensor of natural gas pipeline leakage was reported with wavelength modulation and harmonic signals detection technology. With many materials as reflector used and field locale background simulated,the detection of gas leakage was preformed and better detection limit was got. The sensor is portable with only 5 kg weight.

As we know,the intrinsic gain spectrum characteristics of broadband tellurite-based fiber amplifier(EDTFA)is not flat,so we designed a kind of dual-stage structure with a gain equalization filter between fibers. The theoretical simulation result shows that the fiber with 4000 ppm Er3+ concentration achieved a gain of 24 dB and noise figure of 5.5 dB with a slight gain excursion of 1 dB and the fiber with 6000 ppm Er3+ concentration also achieved a gain of 24 dB and noise figure of 5 dB with a slight gain excursion of 1 dB over a wide wavelength range of 1536～1608 nm through designing certain filters. The dual-stage EDTFA can meet the demand of WDM system after optimization.

Polarization modulating effect was analyzed theoretically for pulling process of fused biconical taper fiber coupler. Geometrical and stressed birefringence caused different propagation constant for symmetric and antisymetric modes on x polarization and y polarization in coupling region. Therefore,it resulted in different coupling spatial period of two polarization orientation,with phase difference. The polarization beam splitting function was realized when the phase difference reached π. Also polarization beamsplitters were built in practice,with 16.5 dB extinction ration.

A novel interferometer,which directs to measure and pick up micro-vibration signal free of distortion,is proposed. The system is based on Michelson interferometer. It uses a fiber laser with narrow linewidth as light source,and adopts homodyne demodulation with phase generated carrier scheme to restore signal. The frequency response range is effectively widened through optimizing the driving circuit of PZT,which is used as phase modulator. And the signal to noise ratio(SNR)is increased with a phase shifter introduced. The system has a good linearity in the frequency range from 50 Hz to 4 kHz. The SNR and harmonic suppression ratio of output signal is 60 dB and 50 dB respectively. The sensitivity of the system is 1×10－5rad/Hz1/2.

The terahertz spectra of architectural materials including soil,stone,brick,cement and wood were studied experimentally. The results show that the terahertz radiation can pass through these materials. Terahertz radiation has a good future in the field of security inspection.

Semiconductor ZnO nanowires embedded in anodic alumina membranes were fabricated by generating alumina templates with nanochannels,electrodepositing Zn in them,and then oxidizing the Zn nanowire arrays. Their microstructures were characterized by scanning electron microscopy and X-ray diffraction spectrum. The results indicate that the polycrystalline ZnO nanowires were uniformly assembled into the hexagonally ordered nanochannels of anodic alumina membranes.

Nanocrystalline Si clusters can be formed in thermally annealed a-Si: H films. Using different characterizing techniques such as micro-Raman scattering,and X-ray diffraction,we have found nc-Si clusters distribute uniformly in the amorphous matrix of the annealed films with typical sizes in the range of 1.6～15 nm in diameter. The sizes of these silicon particles change sensitively with the temperature ramp rate applied during thermal annealing.

The principle of colourimetric temperature measurement using NIRCCD was introduced,the selection method of minimal band width of filter slice and two colour wavelength are discussed in detail,and an ideal combination of wavelength in a given range of temperature is obtained by Matlab simulation.

Serial interface is one of the major communication modes between microcomputer and peripheral equipment. Serial communication plays a very important role in the data transmission. In this communication mode only two signal lines are needed for unidirectional data transmission and can be operated simply. The serial control and transmission are accomplished by applying the McBSP serial mode in DSP. The data and instruction transmission are accepted by applying Object Oriented language VC++. This method has been applied in the technology of laser alarming detection and its efficiency has been proved by experieIrice.