Coulomb blockade behaviors in individual Au nanoparticles as observed through noncontact atomic force spectroscopy at room temperature

• Published in: Nanotechnology Vol. 23; no. 18; p. 185704
• Main Authors: Hattori, Shigeki, Kano, Shinya, Azuma, Yasuo, Tanaka, Daisuke, Sakamoto, Masanori, Teranishi, Toshiharu, Majima, Yutaka
• Format: Journal Article
• Language: English
• Published: England IOP Publishing 11.05.2012
• Subjects: Atomic beam spectroscopy; Atomic structure; Blocking; Coulomb friction; Gold; Nanoparticles; Spectroscopy; Voltage
• ISSN: 0957-4484; 1361-6528
• DOI: 10.1088/0957-4484/23/18/185704

Coulomb blockade behaviors in individual Au nanoparticles of 2 nm core diameter in double-barrier structures have been studied by means of noncontact atomic force spectroscopy (NC-AFS) at room temperature. The Au nanoparticles with a 1-decanethiol ligand were chemisorbed by 1,10-decanedithiol molecules of a mixed 1-octanethiol/1,10-decanedithiol self-assembled monolayer coated on a Au(111) surface; these particles were observed through NC-AFS. NC-AFS measurements of the cantilever frequency shift-sample voltage (Δf-VS) curves were sequentially conducted on three Au nanoparticles under the same experimental conditions; the Δf-VS curves were found to deviate from the parabolic (ΔfN) curve in the cases where no extra charge existed on the Au core. The experimental ΔfCB(=Δf − ΔfN) and ΔfCB V curves agree well with the theoretical curves obtained using a golden-rule calculation and the same parabolic parameters. All the results, through NC-AFS, suggest Coulomb blockade behaviors in the Au nanoparticles at room temperature.