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Register a new userSuperconducting single-mode contact as a microwave-activated quantum interferometer
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Added by
Niklas I:son Lundin
Publication date
1998
fields
Physics
and research's language is
English
Authors
L. Y. Gorelik
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The dynamics of a superconducting quantum point contact biased at subgap voltages is shown to be strongly affected by a microwave electromagnetic field. Interference among a sequence of temporally localized, microwave-induced Landau-Zener transitions between current carrying Andreev levels results in energy absorption and in an increase of the subgap current by several orders of magnitude. The contact is an interferometer in the sense that the current is an oscillatory function of the inverse bias voltage. Possible applications to Andreev-level spectroscopy and microwave detection are discussed.
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