ISSN:
1432-0630
Keywords:
PACS: 07.79.-v; 72.15.-v; 75.70.-Kw
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
,
Physics
Notes:
In low-temperature tranport measurements, we observed two distinct magnetization-dependent features. Before magnetization, aperiodic conductance oscillations against gate voltage sweep were observed: after magnetization, periodic and reproducible oscillations were recorded. In studying the current-voltage characteristics, we observed Coulomb blockade-like features. The Coulomb gap is reduced to about a half when external magnetic fields of ±5000 Gs are applied, which seems to indicate expansion of the dot size. To study the origin of those transport features, magnetic force microscopy (MFM) measurements have been made for similar Ni dot samples at ambient conditions. MFM observation suggests preliminary domain wall formation inside the dot before magnetization. This then disappears after magnetization, implying a single domain formation for the entire dot. On the basis of those results, we propose a domain-related transport model which essentially interprets the observed transport properties.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s003390051304
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