Determination of the local contact potential difference of PTCDA on NaCl: a comparison of techniques

Burke, S. A.; LeDue, Jeffrey; Miyahara, Yoichi; Topple, Jessica M.; Fostner, Shawn; Grütter, Peter

doi:10.1088/0957-4484/20/26/264012

Cited by 53 publications

(56 citation statements)

References 19 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…At equivalent height, the Madelung surface potential is 0.14 V [9]. This resonancelike effect has been predicted theoretically [10] and reported experimentally [19]. It relies on a subtle balance between short-range and long-range electrostatic forces, both weighting in the manner the LCPD is compensated.…”

supporting

confidence: 55%

Understanding the Atomic-Scale Contrast in Kelvin Probe Force Microscopy

et al. 2009

View full text Add to dashboard Cite

A numerical analysis of the origin of the atomic-scale contrast in Kelvin probe force microscopy is presented. Atomistic simulations of the tip-sample interaction force field have been combined with a noncontact atomic force microscope simulator including a Kelvin module. The implementation mimics recent experimental results on the (001) surface of a bulk alkali halide crystal for which simultaneous atomic-scale topographical and contact potential difference contrasts were reported. The local contact potential difference does reflect the periodicity of the ionic crystal, but not the magnitude of its Madelung surface potential. The imaging mechanism relies on the induced polarization of the ions at the tip-surface interface owing to the modulation of the applied bias voltage. Our findings are in excellent agreement with previous theoretical expectations and experimental observations.

show abstract

supporting

confidence: 55%

Understanding the Atomic-Scale Contrast in Kelvin Probe Force Microscopy

et al. 2009

View full text Add to dashboard Cite

show abstract

“…The AFM-derived technique of Kelvin probe force spectroscopy 41 can be used to map out the electrostatic potential in front of a surface. [42][43][44][45][46][47][48] In the case of single molecules, it can be used to map out their quadrupole moment, 49 the charge distribution inside molecules, 50 or the polarity of bonds. 51 a) Electronic mail: liu@dcb.unibe.ch b) Electronic mail: jascha.repp@ur.de Such charge mapping has been shown to be sensitive enough to detect charging of individual atoms by a single electron.…”

Section: General Introductionmentioning

confidence: 99%

Forces from periodic charging of adsorbed molecules

Kocić

Decurtins

Liu

et al. 2017

The Journal of Chemical Physics

View full text Add to dashboard Cite

In a recent publication [Kocić et al., Nano Lett. 15, 4406 (2015)], it was shown that gating of molecular levels in the field of an oscillating tip of an atomic force microscope can enable a periodic charging of individual molecules synchronized to the tip’s oscillatory motion. Here we discuss further implications of such measurements, namely, how the force difference associated with the single-electron charging manifests itself in atomic force microscopy images and how it can be detected as a function of tip-sample distance. Moreover, we discuss how the critical voltage for the charge-state transition depends on distance and how that relates to the local contact potential difference. These measurements allow also for an estimate of the absolute tip-sample distance.

show abstract

“…While this method requires a much higher ac voltage amplitude, it offers higher spatial resolution because the resonance frequency shift is determined by the electrostatic force gradient with respect to the tip-sample distance rather than the force itself [3,4,7].…”

Section: Introductionmentioning

confidence: 99%

Kelvin Probe Force Microscopy by Dissipative Electrostatic Force Modulation

et al. 2015

View full text Add to dashboard Cite

We report a new experimental technique for Kelvin probe force microscopy (KPFM) using the dissipation signal of frequency modulation atomic force microscopy for bias voltage feedback. It features a simple implementation and faster scanning as it requires no low frequency modulation. The dissipation is caused by the oscillating electrostatic force that is coherent with the tip oscillation, which is induced by a sinusoidally oscillating voltage applied between the tip and sample. We analyzed the effect of the phase of the oscillating force on the frequency shift and dissipation and found that the relative phase of 90 • that causes only the dissipation is the most appropriate for KPFM measurements. The present technique requires a significantly smaller ac voltage amplitude by virtue of enhanced force detection due to the resonance enhancement and the use of fundamental flexural mode oscillation for electrostatic force detection. This feature will be of great importance in the electrical characterizations of technically relevant materials whose electrical properties are influenced by the externally applied electric field as is the case in semiconductor electronic devices.

show abstract

Determination of the local contact potential difference of PTCDA on NaCl: a comparison of techniques

Cited by 53 publications

References 19 publications

Understanding the Atomic-Scale Contrast in Kelvin Probe Force Microscopy

Understanding the Atomic-Scale Contrast in Kelvin Probe Force Microscopy

Forces from periodic charging of adsorbed molecules

Kelvin Probe Force Microscopy by Dissipative Electrostatic Force Modulation

Contact Info

Product

Resources

About