A superconducting field-effect switch.
We report here on a novel realization of a field-effect device that allows switching between insulating and superconducting states, which is the widest possible variation of electrical properties of a material. We chose C(60) as the active material because of its low surface state density and observed superconductivity in alkali metal-doped C(60). We induced three electrons per C(60) molecule in the topmost molecular layer of a crystal with the field-effect device, creating a superconducting switch operating up to 11 kelvin. An insulator was thereby transformed into a superconductor. This technique offers new opportunities for the study of superconductivity as a function of carrier concentration.
Schon
J H
JH
Bell Laboratories, Lucent Technologies, 600 Mountain Avenue, Murray Hill, NJ 07974, USA. Departments of Chemistry and Physics and Advanced Carbon Materials Center, University of Kentucky, Lexington, KY 40506, USA.
Kloc
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C
Haddon
R C
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Batlogg
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