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Experimental Heat-Bath Cooling of Spins

Gilles Brassard·Yuval Elias·Jose M. Fernandez·Haggai Gilboa·Jonathan A. Jones·Tal Mor·Yossi Weinstein·Li Xiao
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Abstract

Algorithmic cooling is a novel technique to generate ensembles of highly polarized spins, which could significantly improve the signal strength in Nuclear Magnetic Resonance (NMR) spectroscopy. It combines reversible (entropy-preserving) manipulations and irreversible controlled interactions with the environment, using simple quantum computing techniques to increase spin polarization far beyond the Shannon entropy-conservation bound. Notably, thermalization is beneficially employed as an integral part of the cooling scheme, contrary to its ordinary destructive implications. We report the first cooling experiments bypassing Shannon's entropy-conservation bound, performed on a standard liquid-state NMR spectrometer. We believe that this experimental success could pave the way for the first near-future application of quantum computing devices.

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Gilles Brassard, Yuval Elias, Jose M. Fernandez, Haggai Gilboa, Jonathan A. Jones, Tal Mor, Yossi Weinstein, Li Xiao. 2005-11-16. Experimental Heat-Bath Cooling of Spins. https://arxiv.org/abs/quant-ph/0511156

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