ion for the single-particle electronic properties as an adapted material-specific input for a numerical renormalization group approach for accurately determining the electronic properties of a NTCDA molecule on Ag(111) as a challenging sample system for our theory. Our analysis shows that the mismatch between the ab-initio many-body calculation of the tunnel current in the absence of any electron-phonon coupling to the experiment scanning tunneling spectra can be resolved by including two mechanisms: (i) a strong unconventional Holstein term on the local substrate orbital leads to reduction of the Kondo temperature and (ii) a different electron-vibrational coupling to the tunneling matrix element is responsible for inelastic steps in the $dI/dV$ curve at finite frequencies.'
author:
- Fabian Eickhoff
- Elena Kolodzeiski
- Taner Esat
- Norman Fournier
- Christian Wagner
- Thorsten Deilmann
- Ruslan Temirov
- Michael Rohlfing
- 'F. Stefan Tautz'
- 'Frithjof B. Anders'
title: 'Inelastic electron tunneling spectroscopy for probing strongly correlated many-body systems by scanning tunneling microscopy'
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Introduction
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The investigation of phonons and molecular vibrations by inelastic electron tunneling spectroscopy dates back more than 50 years [@JaklevicLambe1966; @MolecularVibrationTunnel1968]. For example, point contact spectroscopy [@PCSreview1989] has been successfully used to measure the electron-phonon coupling function that enters the Migdal-Eliashberg theory [@McMillanTc1968; @AllenMitrovic] of superconductivity. Recently, the increasing relevance of quantum nanoscience [@Khajetoorians2011; @Baumann2015; @Donati2016; @Natterer2017; @Esat2018; @Cocker2016; @Doppagne2018; @Kimura2019; @Wagner2019] revitalizes the interest in vibrational inelastic electron tunneling spectroscopy (IETS) of molecules adsorbed on solid surfaces [@Stipe1998; @Guo2016; @Wegner2013; @Burema2013] or contacted in transport junctions [@Kim2011a; @Vitali2010; @Meierott2017; @Bruot2012; @Sukegawa2014]. While the fundamental