量子纠缠态在量子通信中起着非常重要的作用，现已有许多量子系统都可以产生量子纠缠态。光子系统由于其自身的优势，例如：传输速度快、易于操作、多自由度等，常用于编码和传输量子信息，完成量子信息处理的许多任务。许多量子通信协议执行的一个前提条件是需要通信参与者共享高保真度的量子纠缠态，但是纠缠态在量子信道中的传输过程，会受到外界环境噪声的影响，使其变成非最大纠缠态，甚至变成混合态，导致量子通信任务的失败，通信的参与者不能得到正确的量子信息。因此光量子态在量子信道中的抗噪声传输的研究对于量子态的保真传输和未来远距离的量子网络的构建具有重要的研究意义。本文主要对光量子态在噪声条件下的抗噪声保真传输与通信进行了相关的研究，主要包括四个方面：

       一、我们对在非共享坐标系下纠缠态的避错传输进行了研究，提出了在非共享坐标系下基于线性光学元件和主动控制元件普克尔盒的纠缠态避错传输方案。这两个方案都不需要辅助粒子，减少了对于信道损耗的敏感性，用稳定的时间自由度代替了易受到空间扰动影响的横向空间模式，并且这些方案都可以从两粒子纠缠态扩展到N粒子GHZ态。对于第一个方案由于只需要线性光学元件，使得该方案更加简便和有效，在实验上易于实现。而利用被动线性光学元件纠缠避错传输方案中保真度的提高是以成功的效率作为代价，那么基于线性元件方案的成功概率是不能达到100%，我们进一步通过引入主动偏振控制元件普克尔盒（Pockels cells）提出改进方案，使得成功的效率进一步提高到100%。

       二、我们提出了利用光子的偏振和横向空间模式这两个自由度对抗联合旋转噪声的量子密钥分发方案。通过利用光子的偏振和横向空间这两个自由度构建单光子Bell 态和超纠缠态，将其作为两组互无偏的基矢并扩展在无消相干子空间中消除信道中联合旋转噪声的影响，最后分别用于构造逻辑比特执行量子密钥分发的方案。我们的方案只需要利用两个粒子构建逻辑比特，相比于三粒子和多粒子的方案，降低了通信中多粒子引起的损耗，提高了量子的传输效率。此外，由于构建逻辑比特的两个光子的形式具有对称性，因此我们的方案对于光子的顺序是没有严格的要求，这就使我们的方案在实验中更容易执行。

       三、我们提出了基于线性光学元件修正单光子Bell态的比特错误的方案并将其扩展到逻辑纠缠态纯化。这里的逻辑比特是单光子Bell态，由单光子的偏振和横向空间两个自由度构成的。对于单光子Bell态的比特错误，我们提出利用线性光学元件和路径信息修正单光子Bell态中的比特和相位翻转错误，并且修正后的保真度可以达到100%。对于单光子Bell态构造的逻辑纠缠态中的逻辑比特翻转和相位错误，我们可以将上述方案通过利用宇称检测可以扩展到逻辑纠缠态的纯化，进一步完成逻辑纠缠态中的逻辑比特翻转和相位错误纯化。

       四、我们提出了逻辑纠缠态的浓缩方案。该逻辑比特与之前方案相同，它对联合旋转噪声具有鲁棒性，但是由于逻辑纠缠态的制备可能不完美或者在外界噪声的影响下变为非最大逻辑纠缠态。在我们的方案中通过利用带有附加镜的马赫-曾德干涉仪、宇称测量和后选择操作，通信参与方可以从非最大逻辑纠缠态中提取最大逻辑纠缠态。我们的这个方案只需要线性光学元件，在实验上易于实现，并且该方案可以扩展到N粒子逻辑纠缠态浓缩。

    Quantum entangled states play a key role in quantum communication and they have been generated in many quantum systems. Photonic systems have many advantages due to their own characteristics, such as high speed of transmission, easy operation, multiple degrees of freedom. Therefore the photons are often used to encode and transmit the information, and accomplish many tasks of quantum information processing. A prerequisite for the implementation of many quantum communication protocols is that parties of communication need to share the high-fidelity quantum entangled state. However, during the transmission process of entangled states in the quantum channel, the entangled states are vulnerable to environmental noise, which makes it become non-maximally entangled states or even become mixed states, leading to the failure of quantum communication task. As a result, the communicating parties cannot obtain the correct quantum information. Therefore, the research for anti-noise transmission of entangled quantum states in quantum channels is of great significance to the fidelity transmission of quantum states and the construction of distant long-distance quantum networks. In this thesis, we mainly focus on the faithful transmission and communication of entangled states under environment noise conditions, including four aspects：
    Firstly, the error-rejecting transmission of entangled photons state is researched when the reference frames of parties cannot be calibrated. We proposed alignment-free polarization-entanglement transmission schemes based on the linear optical elements and active control elements Pockels cells. These schemes don't require auxiliary particles and reduce the sensitivity to channel loss. What's more, the schemes use the stable time-bin to replace the environment-sensitive transverse spatial modes and can be extended to the case of N-particle Greenberger-Horne-Zeilinger (GHZ) state transmission.  For the first scheme, it is executed only using linear optical elements, which make it more simple and effective, and easy to implement experimentally. Because the fidelity of scheme can be improved at the expense of success probability, the success probability cannot reach 100% using passive linear optical elements. The improved scheme was proposed by introducing active polarization control elements (Pockels cells), the success probability can be further improved to 100%.
    Secondly, we proposed a quantum key distribution scheme against collective-rotation noise using polarization and transverse spatial modes two degrees of freedom of photons. The polarization and transverse spatial modes of photons are used to construct single-photon Bell states and hyperentangled states as two groups of mutually unbiased bases and are extended in the decoherence-free subspace against collective-rotation noise in the transmission channel. Finally, they are respectively used to construct logical qubits and to execute the quantum key distribution scheme. Compared with the three-particle and multi-particle schemes, our scheme only needs two particles reducing the loss caused by multi-particle and improving the efficiency of quantum transmission. What's more, due to the symmetry of the two photons of the logical qubits, our scheme doesn't strictly require the relative order of the two photons, which makes our scheme easier to implement in the experiment.
    Thirdly, we proposed a scheme for correcting qubit errors of single-photon Bell state based on linear optics and extending it to logical entangled state purification. Here the logical qubits are single-photon Bell states, consisting of polarization and transverse spatial degrees of freedom of a single photon. For the bit-flip and phase-flip errors occurring in single-photon Bell state, our scheme can correct the errors using linear optical elements and path information, and the fidelity after correcting can reach 100%. What's more, for the logical bit-flip and phase-flip errors occurring in logical entangled states, the logical entanglement can be further purified with the parity check measurement.
   Fourthly, we proposed a concentration scheme of logical entanglement state. Here the logical qubits are the same as the previous scheme, which are robust to collective-rotation noise. However, the preparation of the entanglement state is possibly imperfect or logical entanglement state will become a non-maximal logical entanglement state under the influence of environmental noise. In our scheme, the maximally logical entanglement state can be extracted from non-maximal entanglement by the Mach-Zender interferometer with an additional mirror (MZIM), parity measurement and post-selection. Our scheme needs only linear optical elements and is easy to implement in experiment. Moreover, the scheme can be extended to the N-particle logical entangled states concentration.