title: Quantum point contact microscopy.
abstract: We introduce quantum point contact microscopy (QPCM) as a novel method for surface characterization, where the conductance through a quantum point contact formed by a metal atom between the tip of a scanning tunneling microscope and the surface is mapped across the surface. Application of QPCM to copper and gold (111) shows reproducibly atomic resolution, on gold (111) the alternating atomic stacking of the surface reconstruction is observed in real space. The perspectives for chemical sensitivity in QPCM images are demonstrated for an iron-platinum surface alloy where we observe local variations of the transport current due to changes in the chemical environment of the point contact.
authors.affiliation: Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, 70569 Stuttgart, Germany. zhangyonghui02@tsinghua.org.cn
authors.forename: Yong-Hui
authors.initials: YH
authors.lastname: Zhang
authors.forename: Peter
authors.initials: P
authors.lastname: Wahl
authors.forename: Klaus
authors.initials: K
authors.lastname: Kern
mesh_terms: D003300:Copper / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D008670:Metals / Q000737:chemistry; D008853:Microscopy / Q000379:methods*; D016252:Microscopy, Scanning Tunneling / Q000379:methods; D036103:Nanotechnology / Q000379:methods*; D011789:Quantum Theory; D013499:Surface Properties; D013816:Thermodynamics
chemical_list: D008670:Metals; D006046:Gold; D003300:Copper