Zhongguo kexue. Wulixue Lixue Tianwenxue
Quantum networks for implementing locally and conclusively a nonlocal qudit Toffoli gate: Designing and optimizing
Hong LU, LiBing CHEN
Abstract
Local implementation of a nonlocal d-dimensional quantum Toffoli gate is considered. We construct respectively two quantum networks for realizing this nonlocal quantum gate conclusively. The first one is based on Eisert’s insight but follow a different pathway which results in a nonlocal d-dimensional Toffoli gate design. This scheme involves a local d-dimensional three-body interaction, which does not appear naturally in physical system. The other one can improve significantly the local implementation of this nonlocal gate if the target node harnesses a qutrit as a catalyser. In its simplest form this quantum network that does the improved scheme is built entirely of local single-body and two-body elementary gates, and with only 3 two-body elementary gates at the target node. The latter is simpler but conclusive, and more efficient but with less resource, which will make it more feasible with the current experimental technology and more suitable for large-scale quantum network.