Two-Qubit Quantum Gates to Reduce the Quantum Cost of Reversible Circuit

This paper presents a quantum gate library that consists of all possible two-qubit quantum gates which do not produce entangled states. The quantum cost of each two-qubit gate in the proposed library is one. Therefore, these gates can be used to reduce the quantum costs of reversible circuits. Experimental results show a significant reduction of quantum cost in benchmark circuits. The resulting circuits could be further optimized with existing tools, such as quantum template matching.