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arXiv · 1907.12171

Modular Quantum Computation in a Trapped Ion System

Kuan Zhang·Jayne Thompson·Xiang Zhang·Yangchao Shen·Yao Lu·Shuaining Zhang·Jiajun Ma·Vlatko Vedral·Mile Gu·Kihwan Kim
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Abstract

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 $U$. We demonstrate that the algorithm functions correctly irrespective of what unitary $U$ the server implements or how the server specifically realizes $U$. Our experiment involves pioneering techniques to coherently swap qubits encoded within the motional states of a trapped \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.

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Kuan Zhang, Jayne Thompson, Xiang Zhang, Yangchao Shen, Yao Lu, Shuaining Zhang, Jiajun Ma, Vlatko Vedral, Mile Gu, Kihwan Kim. 2019-07-29. Modular Quantum Computation in a Trapped Ion System. https://doi.org/10.1038/s41467-019-12643-2

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