Abstract:
:The design, realization, and test performances of an electronic junction based on single-electron phenomena that works in the air at room temperature are hereby reported. The element consists of an electrochemically etched sharp tungsten stylus over whose tip a nanometer-size crystal was synthesized. Langmuir-Blodgett films of cadmium arachidate were transferred onto the stylus and exposed to a H2S atmosphere to yield CdS nanocrystals (30-50 angstrom in diameter) imbedded into an organic matrix. The stylus, biased with respect to a flat electrode, was brought to the tunnel distance from the film and a constant gap value was maintained by a piezo-electric actuator driven by a feedback circuit fed by the tunneling current. With this set-up, it is possible to measure the behavior of the current flowing through the quantum dot when a bias voltage is applied. Voltage-current characteristics measured in the system displayed single-electron trends such as a Coulomb blockade and Coulomb staircase and revealed capacitance values as small as 10(-19) F.
journal_name
Proc Natl Acad Sci U S Aauthors
Facci P,Erokhin V,Carrara S,Nicolini Cdoi
10.1073/pnas.93.20.10556keywords:
subject
Has Abstractpub_date
1996-10-01 00:00:00pages
10556-9issue
20eissn
0027-8424issn
1091-6490journal_volume
93pub_type
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