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Efficient implementation of selective recoupling in heteronuclear spin systems using Hadamard matrices

Debbie W. Leung·Isaac L. Chuang·Fumiko Yamaguchi·Yoshihisa Yamamoto
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Abstract

We present an efficient scheme which couples any designated pair of spins in heteronuclear spin systems. The scheme is based on the existence of Hadamard matrices. For a system of $n$ spins with pairwise coupling, the scheme concatenates $cn$ intervals of system evolution and uses at most $c n^2$ pulses where $c \approx 1$. Our results demonstrate that, in many systems, selective recoupling is possible with linear overhead, contrary to common speculation that exponential effort is always required.

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Debbie W. Leung, Isaac L. Chuang, Fumiko Yamaguchi, Yoshihisa Yamamoto. 1999-04-28. Efficient implementation of selective recoupling in heteronuclear spin systems using Hadamard matrices. https://doi.org/10.1103/physreva.61.042310

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