| （英） |
In quantum circuit design, reducing T-depth is an important challenge. In quantum circuit design, logic functions are primarily constructed using MCT (Multiple-Control Toffoli) gates. Decomposing methods of MCT gates to reduce T-depth have been studied. Decomposition methods that aim to reduce T-depth, such as those proposed by Abdesaied et al. and Niemann et al., have been suggested. However, these methods do not consider the differences in T-depth values for each bit. In reality, when decomposing MCT gates, the T-depth values differ for each bit, so the existing methods may use bits with large T-depth values when decomposing multiple MCT gates. As a result, the decompositions in the existing methods may not achieve optimal T-depth. In this paper, we propose a method for reducing the maximum T-depth in quantum Boolean circuits by decomposing MCT gates while considering the T-depth values of individual bits. The proposed method reduces T-depth by prioritizing the use of bits with smaller T-depth during the decomposition of MCT gates. Using the proposed method, we reduce the T-depth compared to the existing methods for all circuits tested. |