采用高梯度布里奇曼结合两步密封晶体生长法和光加热高压浮区法分别进行CuxBi2Se3和NbxBi2Se3拓扑超导体大体积单晶生长研究，确定形成完全体超导的成分范围和形成单晶的热力学条件及凝固机制，揭示单晶制备过程工艺参数对晶体相组成、微观结构、成分分布、晶体缺陷等的影响规律，优化晶体生长参数，制备出高质量大体积的CuxBi2Se3和NbxBi2Se3拓扑超导体单晶。深入研究CuxBi2Se3和NbxBi2Se3拓扑超导体晶体结构、电子结构、磁结构、表面态、磁有序转变及电阻率、比热等物理性能，揭示各向异性规律。针对大单晶体，采用μ介子自旋旋转（μSR）实验，探明CuxBi2Se3和Nbxbi2se3中手性自旋三重态超导性或手性p波超导性特征；采用中子散射研究自旋激发、磁谱和磁结构，探明反铁磁、超导和向列序的相互作用关系，为揭示非常规超导的起源提供实验和理论依据。

The proposed project aims to investigate large single crystal growth of CuxBi2Se3 and NbxBi2Se3 topological superconductors by using high gradient Bridgman combined with two-step sealed crystal growth method and optical heating high-pressure floating zone technique. The composition range, thermodynamic conditions and solidification mechanism for the formation of completely superconducting bulk single crystals will be determined. The effects of processing parameters on the phase constitution, microstructure, composition distribution and crystal defects of single crystals will be revealed. High quality large single crystals of CuxBi2Se3 and NbxBi2Se3 topological superconductors will be grown on the basis of optimizing the crystal growth parameters. The crystal structure, electronic structure, magnetic structure, surface state and physical properties, such as magnetic ordering transition, resistivity and specific heat, will be studied to reveal the anisotropy. For the large single crystals, the chiral spin triplet superconductivity or chiral p-wave superconductivity will be examined by muon spin rotation (SR) experiment. Neutron scattering will be performed to investigate the spin excitation, magnetic spectrum and magnetic structure, exploring the interaction between antiferromagnetism, superconductivity and nematic ordering. This work is expected to provide experimental and theoretical support for revealing the origin of unconventional superconductivity.