Detection of ultrafast oscillations in superconducting point contacts by means of supercurrent measurements

We present a microscopic calculation of the nondissipative current through a superconducting quantum point contact coupled to a mechanical oscillator. Using the nonequilibrium Keldysh Green function approach, we determine the current-phase relation. The latter shows that at certain phases, the curre...

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Detalles Bibliográficos
Autores: Avriller, R., Bergeret, F. Sebastian, Pistolesi, F.
Tipo de recurso: artículo
Fecha de publicación:2011
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:dnet:digitalcsic_::6a64059a4cddf0feba6bdf80f6eb2c6a
Acceso en línea:http://hdl.handle.net/10261/50533
Access Level:acceso abierto
Descripción
Sumario:We present a microscopic calculation of the nondissipative current through a superconducting quantum point contact coupled to a mechanical oscillator. Using the nonequilibrium Keldysh Green function approach, we determine the current-phase relation. The latter shows that at certain phases, the current is sharply suppressed. These dips in the current-phase relation provide information about the oscillating frequency and coupling strength of the mechanical oscillator. We also present an effective two-level model from which we obtain analytical expressions describing the position and width of the dips. Our findings are of relevance for nanomechanical resonators based on superconducting materials. © 2011 American Physical Society.