While quantum information processing by nuclear magnetic resonance (NMR) with small number of qubits is well established, implementation of lengthy computations have proved to be difficult due to decoherence/relaxation. In such circumstances, shallow circuits (circuits using parallel computation) may prove to be realistic. Parity and fanout gates are essential to create shallow circuits. In this article we implement inversion-on-equality gate, followed by parity gate and fanout gate in 3-qubit systems by NMR, using evolution under indirect exchange coupling Hamiltonian.
@article{arxiv.quant-ph/0404036,
title = {Quantum Information processing by NMR: Implementation of Inversion-on-equality gate, Parity gate and Fanout gate},
author = {T. Gopinath and Ranabir Das and Anil Kumar},
journal= {arXiv preprint arXiv:quant-ph/0404036},
year = {2007}
}