A general protocol for distributed quantum gates

In distributed quantum computation, quantum remote-controlled gates are used frequently and applied on separate nodes or subsystems of a network. One of the universal and well-known controlled gates is the n-qubit controlled-NOT gate, especially Toffoli gate for the case of three qubits, which are frequently used to synthesize quantum circuits. In this paper, we considered a more general case, an n-qubit controlled-U gate, and present a general protocol for implementing these gates remotely with minimum required resources. Then, the proposed method is applied to implement a Toffoli gate in bipartite and tripartite systems. In this method, we considered cases in which a group of qubits belongs to one subsystem of the network. Then, we improved its consumption resources.

Automated summary

This paper explores the implementation of n-qubit controlled-U gates in distributed quantum computation, proposing a general protocol for remote implementation with minimal resources, and applying it to implement Toffoli gates in bipartite and tripartite systems. By considering the layout and resource allocation of qubits in network subsystems, the method further optimizes the implementation of gates.