Conductance of atom-sized contacts of transition metals at room temperature

• Published in: Surface science Vol. 606; no. 11-12; pp. 928 - 932
• Main Authors: Moriguchi, Y., Yamauchi, K., Kurokawa, S., Sakai, A.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier B.V 01.06.2012; Elsevier
• Subjects: Atom-sized contacts; Breaking; Cobalt; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Conductance; Cross-disciplinary physics: materials science; rheology; Exact sciences and technology; Histograms; Iron; Nickel; Physics; Stability; Transition metals; Ultrahigh vacuum; Conductance; Iron; Nickel; Atom-sized contacts; Cobalt; Transition elements
• ISSN: 0039-6028; 1879-2758
• DOI: 10.1016/j.susc.2012.02.009

Exploiting the mechanically controllable break junction technique, we have measured the conductance of atom-sized contacts of Fe, Co, and Ni at room temperature under ultrahigh vacuum conditions. The conductance histogram of Fe exhibits a broad peak around 2.5G0 (G0≡2e2/h), whereas those of Co and Ni show no conductance peaks. However, the histograms of Co and Ni display different structures: While the Co histogram is simply flat, the Ni histogram reveals an appreciable background. Our experimental results are compared with previous results obtained at cryogenic and room temperatures, and the observed peak missing in our room-temperature histograms of Co and Ni is discussed. ► Room-temperature conductance of Fe, Co, and Ni atom-sized contacts in UHV. ► A conductance peak is found in the histogram of Fe but not in those of Co and Ni. ► The conductance histograms of Ni and Co are featureless but essentially different. ► Our results indirectly prove the proposed contact stabilization in solutions. ► No integer and fractional quantized peaks are observed.