title: Room-temperature single-photon level memory for polarization states.
abstract: An optical quantum memory is a stationary device that is capable of storing and recreating photonic qubits with a higher fidelity than any classical device. Thus far, these two requirements have been fulfilled for polarization qubits in systems based on cold atoms and cryogenically cooled crystals. Here, we report a room-temperature memory capable of storing arbitrary polarization qubits with a signal-to-background ratio higher than 1 and an average fidelity surpassing the classical benchmark for weak laser pulses containing 1.6 photons on average, without taking into account non-unitary operation. Our results demonstrate that a common vapor cell can reach the low background noise levels necessary for polarization qubit storage using single-photon level light, and propels atomic-vapor systems towards a level of functionality akin to other quantum information processing architectures.
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, New York 11794-3800, USA.
authors.forename: Connor
authors.initials: C
authors.lastname: Kupchak
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, New York 11794-3800, USA.
authors.forename: Thomas
authors.initials: T
authors.lastname: Mittiga
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, New York 11794-3800, USA.
authors.forename: Bertus
authors.initials: B
authors.lastname: Jordaan
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, New York 11794-3800, USA.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Namazi
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, New York 11794-3800, USA.
authors.forename: Christian
authors.initials: C
authors.lastname: Nölleke
authors.affiliation: Department of Physics and Astronomy, Stony Brook University, New York 11794-3800, USA.
authors.forename: Eden
authors.initials: E
authors.lastname: Figueroa