title: Time-resolved scattering of a single photon by a single atom.
abstract: Scattering of light by matter has been studied extensively in the past. Yet, the most fundamental process, the scattering of a single photon by a single atom, is largely unexplored. One prominent prediction of quantum optics is the deterministic absorption of a travelling photon by a single atom, provided the photon waveform matches spatially and temporally the time-reversed version of a spontaneously emitted photon. Here we experimentally address this prediction and investigate the influence of the photon's temporal profile on the scattering dynamics using a single trapped atom and heralded single photons. In a time-resolved measurement of atomic excitation we find a 56(11)% increase of the peak excitation by photons with an exponentially rising profile compared with a decaying one. However, the overall scattering probability remains unchanged within the experimental uncertainties. Our results demonstrate that envelope tailoring of single photons enables precise control of the photon-atom interaction.
authors.affiliation: Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore.|Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.
authors.forename: Victor
authors.initials: V
authors.lastname: Leong
authors.affiliation: Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore.
authors.forename: Mathias Alexander
authors.initials: MA
authors.lastname: Seidler
authors.affiliation: Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore.|Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.
authors.forename: Matthias
authors.initials: M
authors.lastname: Steiner
authors.affiliation: Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore.
authors.forename: Alessandro
authors.initials: A
authors.lastname: Cerè
authors.affiliation: Centre for Quantum Technologies, National University of Singapore, 3 Science Drive 2, Singapore 117543, Singapore.|Department of Physics, National University of Singapore, 2 Science Drive 3, Singapore 117542, Singapore.
authors.forename: Christian
authors.identifier: 0000-0003-2190-0684
authors.initials: C
authors.lastname: Kurtsiefer