NONMETALLIC CONDUCTION OF ULTRATHIN GOLD WIRES AT LOW TEMPERATURES
Abstract
Electronic transport in disordered systems has come to be understood within the framework of two theories. They are electron-electron interaction theory and electronic localization theory. These theories make very interesting predictions concerning systems of reduced dimensionality. We have studied the electrical properties of ultrathin wires to test the predictions of these theories. Au wires with diameters as small as 80(ANGSTROM) have been produced by electroplating into etched nuclear tracks in mica. At low temperatures, T, the resistance, R, of the wires increases as T is decreased, and below about 3K, R varies as 1/T(' 1/2). This, along with the magnitude of the rise, is in agreement with previous results for somewhat larger lithographically produced wires. The behavior at higher temperatures, 3-7K, is more complicated than has been observed previously. The observed behavior is not consistent with expectations based on electron-electron interaction theory alone, but can be accounted for, at least qualitatively, by including electronic localization. By varying the thickness of the mica, it was possible to make wires as short as 1.5 (mu)m. The dependence of the resistance rise on the length of the wire is significantly different from that found for lithographically produced wires. The reason for this is not understood.
Degree
Ph.D.
Subject Area
Condensation
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