title: Electron tunneling characteristics of a cubic quantum dot, (PbS)32.
abstract: The electron transport properties of the cubic quantum dot, (PbS)32, are investigated. The stability of the quantum dot has been established by recent scanning tunneling microscope experiments [B. Kiran, A. K. Kandalam, R. Rallabandi, P. Koirala, X. Li, X. Tang, Y. Wang, H. Fairbrother, G. Gantefoer, and K. Bowen, J. Chem. Phys. 136(2), 024317 (2012)]. In spite of the noticeable energy band gap (~2 eV), a relatively high tunneling current for (PbS)32 is predicted affirming the observed bright images for (PbS)32. The calculated I-V characteristics of (PbS)32 are predicted to be substrate-dependent; (PbS)32 on the Au (001) exhibits the molecular diode-like behavior and the unusual negative differential resistance effect, though this is not the case with (PbS)32 on the Au (110). Appearance of the conduction channels associated with the hybridized states of quantum dot and substrate together with their asymmetric distribution at the Fermi level seem to determine the tunneling characteristics of the system.
authors.affiliation: Department of Physics, Michigan Technological University, Houghton, Michigan 49931, USA.
authors.forename: Sanjeev K
authors.initials: SK
authors.lastname: Gupta
authors.affiliation: Department of Physics and Astronomy, Valparaiso University, Valparaiso, Indiana 46383, USA.
authors.forename: Haiying
authors.initials: H
authors.lastname: He
authors.affiliation: Department of Physics, Michigan Technological University, Houghton, Michigan 49931, USA.
authors.forename: Douglas
authors.initials: D
authors.lastname: Banyai
authors.affiliation: Department of Physics, West Chester University of Pennsylvania, West Chester, Pennsylvania 19383, USA.
authors.forename: Anil K
authors.initials: AK
authors.lastname: Kandalam
authors.affiliation: Department of Physics, Michigan Technological University, Houghton, Michigan 49931, USA.
authors.forename: Ravindra
authors.initials: R
authors.lastname: Pandey