中文摘要：

量子电路是实现量子态幺正演化的手段，一位和两位门是构成量子电路的基础。Barenco用基本的两位量子逻辑门实现n位量子逻辑门功能，张登玉在Barenco的工作基础上对用基本的两位量子逻辑门实现n位量子逻辑门功能进行了改进。通过对Baxenco方案和张登玉方案的分析和研究，提出了一个用基本的两位量子逻辑门实现n位量子逻辑门功能的新方案，该方案结构更简单，且所用的两位门更易于实现，同时指出和改正了张文的不太准确的结论。

英文摘要：

Quantum circuits are the tools of realizing the unitary evolution of quantum state, and they are mainly made up of one-bit and two-bit quantum gates. Barenco proposed a method for constructing n-bit quantum gate by using basic two-bit quantum gates in 1995. Zhang proposed the improved method for constructing n-bit quantum gate by using basic two-bit quantum gates in 2001. The method for constructing n-bit quantum gate by using basicstwo-bit quantum gates is proposed by improving the two methods mentioned. The scheme is more simple and easier to implement and the incorrect conclusion by Zhang is amended.