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arXiv · 1710.06180

Submolecular resolution by variation of IETS amplitude and its relation to AFM/STM signal

Bruno de la Torre·Martin Švec·Giuseppe Foti·Ondřej Krejčí·Prokop Hapala·Aran Garcia-Lekue·Thomas Frederiksen·Radek Zbořil·Andrés Arnau·Héctor Vázquez·Pavel Jelínek
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Abstract

Here we show scanning tunnelling microscopy (STM), non-contact atomic force microscopy (AFM) and inelastic electron tunnelling spectroscopy (IETS) measurements on organic molecule with a CO- terminated tip at 5K. The high-resolution contrast observed simultaneously in all channels unam- biguously demonstrates the common imaging mechanism in STM/AFM/IETS, related to the lateral bending of the CO-functionalized tip. The IETS spectroscopy reveals that the submolecular con- trast at 5K consists of both renormalization of vibrational frequency and variation of the amplitude of IETS signal. This finding is also corroborated by first principles simulations. We extend accord- ingly the probe-particle AFM/STM/IETS model to include these two main ingredients necessary to reproduce the high-resolution IETS contrast. We also employ the first principles simulations to get more insight into different response of frustrated translation and rotational modes of CO-tip during imaging.

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Bruno de la Torre, Martin Švec, Giuseppe Foti, Ondřej Krejčí, Prokop Hapala, Aran Garcia-Lekue, Thomas Frederiksen, Radek Zbořil, Andrés Arnau, Héctor Vázquez, Pavel Jelínek. 2017-10-17. Submolecular resolution by variation of IETS amplitude and its relation to AFM/STM signal. https://doi.org/10.1103/physrevlett.119.166001

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