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NMR molecular photography

Anatoly K. Khitrin·Vladimir L. Ermakov·B. M. Fung
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Abstract

A procedure is described for storing a 2D pattern consisting of 32x32 = 1024 bits in a spin state of a molecular system and then retrieving the stored information as a stack of NMR spectra. The system used is a nematic liquid crystal, the protons of which act as spin clusters with strong intramolecular interactions. The technique used is a programmable multi-frequency irradiation with low amplitude. When it is applied to the liquid crystal, a large number of coherent long-lived 1H response signals can be excited, resulting in a spectrum showing many sharp peaks with controllable frequencies and amplitudes. The spectral resolution is enhanced by using a second weak pulse with a 90 phase shift, so that the 1024 bits of information can be retrieved as a set of well-resolved pseudo-2D spectra reproducing the input pattern.

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Anatoly K. Khitrin, Vladimir L. Ermakov, B. M. Fung. 2002-08-21. NMR molecular photography. https://arxiv.org/abs/quant-ph/0208136

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