Modular quantum computation in a trapped ion system

Modern computation relies crucially on modular architectures, breaking a complex algorithm into self-contained subroutines. A client can then call upon a remote server to implement parts of the computation independently via an application programming interface (API). Present APIs relay only classical information. Here we implement a quantum API that enables a client to estimate the absolute value of the trace of a server-provided unitary operation $$U$$ U . We demonstrate that the algorithm functions correctly irrespective of what unitary $$U$$ U the server implements or how the server specifically realizes $$U$$ U . Our experiment involves pioneering techniques to coherently swap qubits encoded within the motional states of a trapped $${}^{171}{{\rm{Yb}}}^{+}\,$$ 171 Yb + ion, controlled on its hyperfine state. This constitutes the first demonstration of modular computation in the quantum regime, providing a step towards scalable, parallelization of quantum computation.

An Algorithm Research of Terminal Key Generation for Mobile Payment

For the limited calculation of mobile device, the difficulty of finding big prime number and the complexity of RSA exponential modular computation, this paper proposes a modified algorithm to find prime numbers in the RSA algorithm. It modifies the method of random numbers generation to improve the efficiency of pre-screening algorithm. To reduce the terminal calculation and accelerate the speed of key-pair generation, it transfers the most time-consuming operation of big prime number modular exponentiation to the servers. Based on the key-pair generation algorithm, this paper finally proposes a terminal registration scheme of mobile payment.