| Autor: |
Olofsson, Linda, Persson, S., Morpurgo, Alberto, Marcus, Charles, Golubev, Dimitri, Gunnarsson, Linda, Yao, Yirmin |
| Zdroj: |
Journal of Low Temperature Physics; Mar2000, Vol. 118 Issue 5/6, p343-353, 11p |
| Abstrakt: |
Single electron tunneling devices were made by combiningstandard electron beam lithography and the self-assembly ofchemically synthesized gold clusters. These clusters, withdiameters from 2 to 5 nm, were captured in a 5–10 nm gapbetween two gold electrodes. The gold particles as well as theelectrodes were covered with self-assembled monolayers (SAM)of organic molecules which served as tunnel barriers.Operating devices show a suppressed current due to the Coulombblockade of tunneling at room temperature. When cooled to4.2 K, a Coulomb staircase was observed. By applying a voltageto an oxidized aluminum gate beneath the electrodes and thetrapped gold cluster the current voltage characteristics weremodulated. Anomalous effects are observed such as constantcurrent plateaus whose positions are gate-voltage dependent.An electrodeposition method for gold has been used tofabricate gaps between electrodes smaller than 2 nm. A self-assembled monolayer was used successfully on the electrodes inorder to prevent the gold atoms from migrating on the surfacebetween the electrodes and thereby short-circuiting thejunction. The conductance of such a tunnel junction has beenmeasured and compared to the theory with good agreement. Fromthis comparison the capacitance of the junction was estimated,and we could use that value to calculate a rough estimation ofthe distance between the electrodes. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
Full text from SpringerLink