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Warp-Drive Quantum Computation

Mikio Nakahara·Juha J. Vartiainen·Yasushi Kondo·Shogo Tanimura·Kazuya Hata
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Abstract

Recently it has been shown that time-optimal quantum computation is attained by using the Cartan decomposition of a unitary matrix. We extend this approach by noting that the unitary group is compact. This allows us to reduce the execution time of a quantum algorithm $U_{\rm alg}$ further by adding an extra gate $W$ to it. This gate $W$ sends $U_{\rm alg}$ to another algorithm $WU_{\rm alg}$ which is executable in a shorter time than $U_{\rm alg}$. We call this technique warp-drive. Here we show both theoretically and experimentally that the execution time of Grover's algorithm is reduced in two-qubit NMR quantum computer. Warp-drive is potentially a powerful tool in accelerating algorithms and reducing the errors in any realization. of a quantum computer

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Mikio Nakahara, Juha J. Vartiainen, Yasushi Kondo, Shogo Tanimura, Kazuya Hata. 2004-12-02. Warp-Drive Quantum Computation. https://arxiv.org/abs/quant-ph/0411153

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