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arXiv · 2203.11161

Power-law scaling of correlations in statistically polarised nano-NMR

Nicolas Staudenmaier·Anjusha Vijayakumar-Sreeja·Santiago Oviedo-Casado·Genko Genov·Daniel Cohen·Daniel Dulog·Thomas Unden·Nico Striegler·Alastair Marshall·Jochen Scheuer·Christoph Findler·Johannes Lang·Ilai Schwartz·Philipp Neumann·Alex Retzker·Fedor Jelezko
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Abstract

Diffusion noise is a major source of spectral line broadening in liquid state nano-scale nuclear magnetic resonance with shallow nitrogen-vacancy centres, whose main consequence is a limited spectral resolution. This limitation arises by virtue of the widely accepted assumption that nuclear spin signal correlations decay exponentially in nano-NMR. However, a more accurate analysis of diffusion shows that correlations survive for a longer time due to a power-law scaling, yielding the possibility for improved resolution and altering our understanding of diffusion at the nano-scale. Nevertheless, such behaviour remains to be demonstrated in experiments. Using three different experimental setups and disparate measurement techniques, we present overwhelming evidence of power-law decay of correlations. These result in sharp-peaked spectral lines, for which diffusion broadening need not be a limitation to resolution.

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Nicolas Staudenmaier, Anjusha Vijayakumar-Sreeja, Santiago Oviedo-Casado, Genko Genov, Daniel Cohen, Daniel Dulog, Thomas Unden, Nico Striegler, Alastair Marshall, Jochen Scheuer, Christoph Findler, Johannes Lang, Ilai Schwartz, Philipp Neumann, Alex Retzker, Fedor Jelezko. 2022-03-21. Power-law scaling of correlations in statistically polarised nano-NMR. https://doi.org/10.1038/s41534-022-00632-1

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