Force Field Analysis Suggests a Lowering of Diffusion Barriers in Atomic Manipulation Due to Presence of STM Tip
| Autor: | Norio Okabayashi, Ferdinand Huber, Franz J. Giessibl, Matthias Emmrich, Maximilian Schneiderbauer, Alfred J. Weymouth |
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| Jazyk: | němčina |
| Rok vydání: | 2015 |
| Předmět: |
Materials science
Liquid helium Electrostatic force microscope ddc:530 General Physics and Astronomy Biasing Conductive atomic force microscopy 530 Physik law.invention Superposition principle law Molecule 66.35.+a Atomic physics Scanning tunneling microscope 68.37.Ef Non-contact atomic force microscopy 68.37.Ps |
| Popis: | We study the physics of atomic manipulation of CO on a Cu(111) surface by combined scanning tunneling microscopy and atomic force microscopy at liquid helium temperatures. In atomic manipulation, an adsorbed atom or molecule is arranged on the surface using the interaction of the adsorbate with substrate and tip. While previous experiments are consistent with a linear superposition model of tip and substrate forces, we find that the force threshold depends on the force field of the tip. Here, we use carbon monoxide front atom identification (COFI) to characterize the tip’s force field. Tips that show COFI profiles with an attractive center can manipulate CO in any direction while tips with a repulsive center can only manipulate in certain directions. The force thresholds are independent of bias voltage in a range from 1 to 10 mV and independent of temperature in a range of 4.5 to 7.5 K. |
| Databáze: | OpenAIRE |
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