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arXiv · 1403.7035

Nuclear and electronic resonance spectroscopy of single molecules by radio-frequency scanning tunnelling microscopy

Stefan Müllegger·Stefano Tebi·Amal K. Das·Wolfgang Schöfberger·Felix Faschinger·Reinhold Koch
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Abstract

The ongoing miniaturization in nanoscience and -technology challenges the sensitivity and selectivity of experimental analysis methods to the ultimate level of single atoms and molecules. A promising new approach, addressed here, focuses on the combination of two well-established complementary techniques that have proven to be very successful in their own fields: (i) low-temperature scanning tunneling microscopy (STM), offering high spatial resolution for imaging and spectroscopy together with the capability of manipulating single atoms and molecules in a well-controlled manner; (ii) radio-frequency (rf) magnetic resonance techniques, providing paramount analytical power based on a high energy resolution combined with the versatility of being sensitive to a great variety of different properties of matter. Here, we demonstrate the successful resonant excitation and detection of nuclear and electronic magnetic transitions of a single quantum spin in a single molecule by rf tunneling of electrons applied through the tip of a modified STM instrument operated at 5 K. The presented rf-STM approach allows the unrivalled spectroscopic investigation of electronic hyperfine levels in single molecules with simultaneous sub-molecular spatial resolution. The achieved single-spin sensitivity represents a ten orders of magnitude improvement compared to existing methods of magnetic resonance - offering, atom-by-atom, unprecedented analytical power and spin control with impact to physics, chemistry, biology, medicine, nanoscience and -technology.

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Stefan Müllegger, Stefano Tebi, Amal K. Das, Wolfgang Schöfberger, Felix Faschinger, Reinhold Koch. 2014-03-27. Nuclear and electronic resonance spectroscopy of single molecules by radio-frequency scanning tunnelling microscopy. https://arxiv.org/abs/1403.7035

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