title: Single-photon transistor mediated by interstate Rydberg interactions.
abstract: We report on the realization of an all-optical transistor by mapping gate and source photons into strongly interacting Rydberg excitations with different principal quantum numbers in an ultracold atomic ensemble. We obtain a record switch contrast of 40% for a coherent gate input with mean photon number one and demonstrate attenuation of source transmission by over ten photons with a single gate photon. We use our optical transistor to demonstrate the nondestructive detection of a single Rydberg atom with a fidelity of 0.72(4).
authors.affiliation: 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Gorniaczyk
authors.affiliation: 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
authors.forename: C
authors.initials: C
authors.lastname: Tresp
authors.affiliation: 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
authors.forename: J
authors.initials: J
authors.lastname: Schmidt
authors.affiliation: 3. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
authors.forename: H
authors.initials: H
authors.lastname: Fedder
authors.affiliation: 5. Physikalisches Institut, Universität Stuttgart, Pfaffenwaldring 57, 70569 Stuttgart, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Hofferberth