title: Direct measurement of the Josephson supercurrent in an ultrasmall Josephson junction.
abstract: We have measured the supercurrent flowing through a nonhysteretic, ultrasmall, voltage-biased Josephson junction. In contrast with experiments performed so far on hysteretic Josephson junctions, we find a supercurrent peak whose maximum I(s max) increases as the temperature T decreases. The asymptotic T = 0 value of I(s max) agrees with the junction Ambegaokar-Baratoff critical current, as predicted by theory.
authors.affiliation: Service de Physique de l'Etat Condensé, CEA-Saclay, F-91191 Gif-sur-Yvette, France.
authors.forename: A
authors.initials: A
authors.lastname: Steinbach
authors.forename: P
authors.initials: P
authors.lastname: Joyez
authors.forename: A
authors.initials: A
authors.lastname: Cottet
authors.forename: D
authors.initials: D
authors.lastname: Esteve
authors.forename: M H
authors.initials: MH
authors.lastname: Devoret
authors.forename: M E
authors.initials: ME
authors.lastname: Huber
authors.forename: J M
authors.initials: JM
authors.lastname: Martinis