705 research outputs found

    Metal containing polymers from cyclic tetrameric phenylphosphonitrilamides Patent

    Get PDF
    Chemical synthesis of thermally stable organometallic polymers with divalent metal ion and tetraphenylphosphonitrilic unit

    Synthesis of linear, double chain, ladder polymers from substituted tetraphosphonitriles Quarterly progress report, Jun. - Aug. 1966

    Get PDF
    Synthesis of linear, double-chain, ladder polymers from substituted tetraphosphonitrile

    Synthesis of linear, double chain ladder polymers from substituted tetraphosphonitriles Annual report, 3 May 1965 - 2 May 1966

    Get PDF
    Synthesis of linear, double-chain ladder polymers from substituted tetraphosphonitrile

    Synthesis of linear, double chain, ladder polymers from substituted tetraphosphonitriles Quarterly report, Sep. - Nov. 1966

    Get PDF
    Synthesis of linear, double chain ladder polymers from substituted tetraphosphonitrile

    1/f noise of Josephson-junction-embedded microwave resonators at single photon energies and millikelvin temperatures

    Full text link
    We present measurements of 1/f frequency noise in both linear and Josephson-junction-embedded superconducting aluminum resonators in the low power, low temperature regime - typical operating conditions for superconducting qubits. The addition of the Josephson junction does not result in additional frequency noise, thereby placing an upper limit for fractional critical current fluctuations of 10−810^{-8} (Hz−1/2^{-1/2}) at 1 Hz for sub-micron, shadow evaporated junctions. These values imply a minimum dephasing time for a superconducting qubit due to critical current noise of 40 -- 1400 μ\mus depending on qubit architecture. Occasionally, at temperatures above 50 mK, we observe the activation of individual fluctuators which increase the level of noise significantly and exhibit Lorentzian spectra

    Dispersion management using betatron resonances in an ultracold-atom storage ring

    Full text link
    Specific velocities of particles circulating in a storage ring can lead to betatron resonances at which static perturbations of the particles' orbit yield large transverse (betatron) oscillations. We have observed betatron resonances in an ultracold-atom storage ring by direct observation of betatron motion. These resonances caused a near-elimination of the longitudinal dispersion of atomic beams propagating at resonant velocities, an effect which can improve the performance of atom interferometric devices. Both the resonant velocities and the strength of the resonances were varied by deliberate modifications to the storage ring.Comment: 4 pages, 5 figures. Also available at http://physics.berkeley.edu/research/ultracol

    Quantum State Sensitivity of an Autoresonant Superconducting Circuit

    Get PDF
    When a frequency chirped excitation is applied to a classical high-Q nonlinear oscillator, its motion becomes dynamically synchronized to the drive and large oscillation amplitude is observed, provided the drive strength exceeds the critical threshold for autoresonance. We demonstrate that when such an oscillator is strongly coupled to a quantized superconducting qubit, both the effective nonlinearity and the threshold become a non-trivial function of the qubit-oscillator detuning. Moreover, the autoresonant threshold is sensitive to the quantum state of the qubit and may be used to realize a high fidelity, latching readout whose speed is not limited by the oscillator Q.Comment: 5 pages, 4 figure

    Cavity Nonlinear Optics at Low Photon Numbers from Collective Atomic Motion

    Full text link
    We report on Kerr nonlinearity and dispersive optical bistability of a Fabry-Perot optical resonator due to the displacement of ultracold atoms trapped within. In the driven resonator, such collective motion is induced by optical forces acting upon up to 10510^5 87^{87}Rb atoms prepared in the lowest band of a one-dimensional intracavity optical lattice. The longevity of atomic motional coherence allows for strongly nonlinear optics at extremely low cavity photon numbers, as demonstrated by the observation of both branches of optical bistability at photon numbers below unity.Comment: 4 pages, 3 figures. Modifed following reviewer comment
    • …
    corecore