title: Exciton-spin memory with a semiconductor quantum dot molecule.
abstract: We report on a single photon and spin storage device based on a semiconductor quantum dot molecule. Optically excited single electron-hole pairs are trapped within the molecule, and their recombination rate is electrically controlled over 3 orders of magnitude. Single photons are stored up to 1 μs and read out on a subnanosecond time scale. By using resonant excitation, the circular polarization of individual photons is transferred into the spin state of electron-hole pairs with a fidelity above 80%, which does not degrade for storage times up to the 12.5 ns repetition period of the experiment.
authors.affiliation: Toshiba Research Europe Limited, Cambridge Research Laboratory, 208 Science Park, Milton Road, Cambridge, CB4 0GZ, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Boyer de la Giroday
authors.forename: N
authors.initials: N
authors.lastname: Sköld
authors.forename: R M
authors.initials: RM
authors.lastname: Stevenson
authors.forename: I
authors.initials: I
authors.lastname: Farrer
authors.forename: D A
authors.initials: DA
authors.lastname: Ritchie
authors.forename: A J
authors.initials: AJ
authors.lastname: Shields