2013/11/07 by A. O. Sushkov, N. Chisholm, I. Lovchinsky +8 · 1 citation
Physics and Astronomy · #cond-mat.mes-hall #physics.atom-ph #physics.bio-ph #quant-ph
paper · pdf · doi:10.1021/nl502988n
arxiv created 2013/11/07 · arxiv updated 2015/06/17
We demonstrate an all-optical method for magnetic sensing of individual molecules in ambient conditions at room temperature. Our approach is based on shallow nitrogen-vacancy (NV) centers near the surface of a diamond crystal, which we use to detect single paramagnetic molecules covalently attached to the diamond surface. The manipulation and readout of the NV centers is all-optical and provides a sensitive probe of the magnetic field fluctuations stemming from the dynamics of the electronic spins of the attached molecules. As a specific example, we demonstrate detection of a single paramagnetic molecule containing a gadolinium (Gd3+) ion. We confirm single-molecule resolution using optical fluorescence and atomic force microscopy to co-localize one NV center and one Gd3+-containing molecule. Possible applications include nanoscale and in vivo magnetic spectroscopy and imaging of individual molecules.