An integral imaging system based on hierarchical clustering two-dimensional viewpoint synthesis is proposed. In this integral imaging system, a sparse viewpoint image is collected using a motorized translation stage combined with a single camera viewpoint collection method. In order to improve the efficiency of viewpoint collection, a two-dimensional virtual viewpoint synthesis method based on hierarchical clustering is used to realize virtual viewpoint synthesis between images, and the synthesized multi-viewpoint image is used to obtain an elemental image array through pixel mapping. By using pixel mapping to obtain elemental image array, the computational reconstruction process is achieved. Experimental results show that the system can not only meet the high-efficiency three-dimensional information collection, but also improve the resolution quality and increase the application flexibility while ensuring quality of the synthetic viewpoint.

The propagation properties of two incoherent coupled beams in lossy media are investigated. The evolution equations of amplitude, distance, phase and propagation velocity of incoherently coupled beamswith dielectric loss are derived by variational method, then the interaction potential energy and interaction force of two spatial optical solitons are obtained, and the effect of dielectric loss on soliton transmission and interaction is analyzed. It isshown that the dielectric loss slows down the phase change of the soliton, and the loss also makes the interaction of solitons decay exponentially with the propagation distance, while long-distance transmission may lead to the collapse of soliton pairs. It is also shown that the interaction between solitons has a maximum, and when the distance between solitons is greater than a certain value, the two solitons will transmit independently without interference.

A finite-length impulse response (FIR) filter whose tap coefficients are trained using a neural network for compensation of chromatic dispersion in digital coherent optical receivers is proposed. The frequency response is optimal when the square error is minimized. The pulse shaping filter limits the effective bandwidth of the signal. Therefore, the filter can be designed in a narrow frequency band. The simulation system is designed with MATLAB, and the BER performance of the filters in QPSK, 16 QAM and 64 QAM systems is analyzed through numerical simulation. Results show that compared with the time-domain equalization algorithm under the same conditions, when the number of taps is the same, the filter has a better compensation effect, and the increase in the number of taps will not cause the deterioration of the compensation effect. By designing the filter in a narrow frequency band, the number of taps can be reduced by more than 37.5% under the premise of the same compensation effect, which reduces the complexity of the filter hardware implementation and the filter delay.

Ultra-cold atomic spinor Bose-Einstein condensate has many spin textures with different topological properties, which can provide an ideal quantum simulation platform for the study of topological structures in condensed matter physics and particle physics. The Laguerre-Gaussian beam has special spatial structure and carrys a certain orbital angular momentum, which has been used to research spin-texture in ultra-cold atoms. Studying the two-photon Raman process in F=1 three level atom system driven by Laguerre-Gaussian light by numerical simulation can obtain Skyrmion when the initial state is the ferromagnetic phase or the polarization phase under the condition that the beam waist is comparable withthe size of the atomic cloud, and based on that, a numerical method for acquiring precise beam waist can be proposed, which provides a reference for subsequent experiments.

Using high-dimensional maximally entangled quantum states as channels, an asymmetric controlled bidirectional teleportation scheme is proposed and optimized. The senders (Alice and Bob) and the controller (Charlie) secretly share entangled state in advance to construct quantum channel. Once the communication begins, according to the distribution mode of entangled particles and the different choice of measurement basis, Alice and Bob respectively transmit a single-particle state and a two-particle state in high-dimensional space to each other, under the supervision of Charlie. By optimizing the measurement basis, the success probability raised from 1/d to 1 and the asymmetric controlled bidirectional teleportation is implemented successfully. At the same time, it is physically easy to achive by using generalized Bell-basis measurement and single-qubit measurement only. The improved scheme allows Charlie to control both channels, increasing the security of the scheme.

A method of phase-matching three-decoy-state quantum key distribution is proposed with a weak coherent state source. The relevant parameters such as count rate and bit error rate are estimated, and the statistical analysis method of Chernoff bound is used to analyze the transmission performance of the method under the condition of finite data length. The simulation results show that the maximum secure transmission distance of the phase-matching three-decoy-state quantum key distribution scheme can reach 521 km, which is very close to the theoretical limit of the phase-matching infinite-decoy-state protocol of 536 km. As the data length decreases, the transmission performance of the scheme is declined.Even if the data length drops to 107, its maximum secure transmission distance can still reach 502 km.

Device-independent quantum key distribution protocol is one of the most important research directions in the field of quantum information theory in recent years. The security of this kind of protocolsis not based on the perfect state preparation and measurement, thus it can be applied to avoid the blinding attack from intense light and the wavelength attack, which leads to higher security. Device-independent quantum key distribution protocols are based on the Bell inequality, and the classical value violation can be used to guarantee the security. Based on α~~CHSH inequality, the security of device-independent quantum key distribution protocols is investigated in the bit flipped channel model,and the relationship between the final secret key rate with the violation value of α~~CHSH inequality is given.

Quantum non-locality is a necessary resource for quantum information processing. Recently, I3322 inequality, used as a powerful tool for judging non-locality, has attracted much attention. Considering the non-ideal factors in judging non-locality, MATLAB is used to simulate the quantum violation of inequality influenced by an entanglement state, mixed entanglement states, and noise channels. Results show that for an entanglement state, quantum violation is found when the degree of entanglement is larger than a threshold value. For mixed entanglement states, quantum violation is found in larger parameter regions. Under two-Kraus-operator channels, phase diagram relating to quantum violation is found in the noise parameter space. The results are useful to quantum information processing based on I3322 inequality.

Considering security of the protocol and necessity of the controller for quantum communication, a novel controlled quantum secure direct communication protocol is proposed. In the protocol, the controller prepares and distributes channel particles and decides whether to communicate, and the information of the controller plays a great role in operation of the protocol. The security of the protocol and amount of information transmission are improved by using the encoding operation after encryption and introducing auxiliary particles. The information receiver performs unitary operation according to the processed message and obtains secret information by reverse decoding according to the agreed encryption rules. All published information is not directly related to secret information, thus avoiding the problem of information leakage. The analysis results show that the protocol can resist attacks from third parties and eavesdroppers, and its quantum communication efficiency is 28.75%.

In order to further investigate the tripartite remote state preparation (TRSP), a novel scheme different from the existing TRSP types is put forward, which is an extension of the controlled three-party cyclic remote state preparation, and can be modified into a mixed scheme of a bidirectional controlled remote state preparation and a unidirectional one. In this scheme, the generation method of ten-particle entangled channel is given, and it is pointed out that under the control of the supervisor, any two of the three parties can jointly prepare an arbitrary singleparticle state for the third party. The proposed scheme integrates the idea of controlled remote state preparation and joint remote state preparation, and has high security. Moreover, the feed-forward measurement strategy adopted in the scheme makes its success probability 100%. In addition, the controlled-NOT gate, Hadamard gate and Pauli gate as well as single-particle projective measurement involved in this scheme can be realized physically in modern technology.

Linear nearest neighbor (LNN) quantum circuit is an important quantum circuit architecture, which lays a foundation for the physical realization of quantum circuit. In order to construct LNN quantum logic circuits, a linear nearest neighbor logic synthesis algorithm based on pre-evaluation is proposed. In this algorithm, partial non-nearest neighbor quantum circuits are globally reordered firstly, then the reordered quantum circuits are evaluated by heuristic method, and the set of quantum circuits with the lowest nearest neighbor cost is found by computing the minimum chaos value. Finally, SWAP gates are added to convert the quantum circuit to a nearest neighbor structure with the lowest quantum cost. Through pre-evaluation, on the one hand, the algorithm can accurately calculate whether there are redundant SWAP gates that can be deleted in the quantum circuit and delete them. On the other hand, it can minimize the number of SWAP gates added when each non-nearst neighbor quantum gate is converted into LNN quantum gate, and then the quantum circuit with the lowest quantum cost is obtained. The experimental results show that compared with the known algorithm, the proposed algorithm has less average gates, higher optimization rate of quantum cost and a wider application range.

Quantum key distribution (QKD) technology is a new symmetric key distribution technology, which uses random number to generate quantum signal at the transmitter. At present, with the continuous development of high-speed QKD technology, higher requirements are put forward for the speed and reliability of random number source. The overall requirements of high-speed QKD system random number source are summarized in detail, and the 10 Gbps high-speed random number source and real-time self-check scheme based on field programmable gate array (FPGA) are designed and realized. The random number source is realized by using the phase jitter principle. A single random number source is realized by stacking 128 ring oscillators, and then 10 Gbps high-speed random number is generated by parallelization instance. The random data can pass GM/T0005~~2012RandomnessTestSpecification. Then, according to the unique use demand of QKD system for random number, areal-time self-check module of 10 Gbps processing bandwidth is designed and realized, which guarantees the reliability of high-speed random number used by QKD system and provides support for the development of high-speed QKD system.

In order to establish a defect detection system of fused quartz and improve laser-induced damage threshold, a device of insitu measuring fused quartz damage characteristics is designed. It consists of two parts, photothermal scanning measurement and Raman spectral measurement. The experimental results show that, the equipment can not only measure fixed point damage characteristics of fused quartz, but also get the absorption characteristics anddefect distribution of fused quartz by two-dimensional photothermal scanning. Moreover, the Raman spectral information and material modification information caused by laser irradiation could be obtained insitu through the micro Raman spectrum measurement module of the device, which is of great significance to control and evaluate the laser damage characteristics of fused quartz effectively.

Barrier height Φ and ideal factor n are important parameters for forward transport of merged PIN/Schottky (MPS) diodes, and softness factor is one of the indication of MPS reverse recovery. The structure simulation of 6H-SiC based MPS diode is carried out to verify the existence of double barrier and study the effect of temperature on the forward and reverse characteristics. Results show that in forward bias voltage, the barrier height 1 decreases and the barrier height 2 increases with increasing temperature, while both n1 and n2 decrease with increasing temperature. Because there are multiple composite transport mechanisms in the barrier region 1, and thermionic emission transport is the main transport mechanism in the barrier region 2. Under reverse bias voltage, the reverse recovery peak voltage and peak current increase with increasing temperature, but the softness factor gradually approaches 1.

The first-principles pseudo-potential plane wave method is used to calculate the geometric structure, band structure, Mulliken population analysis, differential charge density and optical properties of the new two-dimensional material phosphorene doped with impurities (X=C, Al). Results show that the phosphorene structure is distorted after impurity doping, but structure of the doping system is stable. After C doped, the Fermi energy level enters the valence band, the band gap becomes narrower and it becomes a direct band gap of 0.826 eV. After Al doped, the system becomes an indirect band gap semiconductor with a slightly widened band gap of 0.965 eV. Both Mulliken population analysis and differential charge density analysis show that the charge distribution of the system shifts after doping, charge accumulation occurs near C atom, and charge consumption occurs near Al atom. The optical properties in the (1 0 0) polarization direction are calculated. In the range of red light and infrared light, the capacity of phosphorene material to store electromagnetic energy is reduced after C doped, and the capacity to store electromagnetic energy is enhanced after Al doped. The refractive index n0 decreases after C doped, while the refractive index n0 increases after Al doped. The peaks of absorption coefficient and reflectivity decrease. The phosphorene materials can be used as light storage materials before and after doped. The above results indicate that the photoelectric properties of the phosphorene material can be modulated by C and Al doped according to actual needs.