Structural Studies of Several Ru3 and Ru4 Carbonyl Clusters

The preparation, characterisation and single‐crystal XRD molecular structure determinations of the three Ru₃ carbonyl clusters attached to carbon ligands, Ru₃(μ‐H)₃(μ₃‐CBr)(CO)₉ ( 1 ), Ru₃(μ‐H)(μ‐dppm){μ‐C(OMe)}(CO)₈ ( 2 ) and AuRu₃(μ‐H)₂(μ₃‐C=C=CHPh)(CO)₁₀ ( 3 ) are reported, together with the structures of the tetranuclear hydrido‐carbonyls Ru₄(μ‐H)_4–2x(CO)_11+x(PPh₃) (x = 0 4 , 1 5 ).     

Demonstration of a simple entangling optical gate and its use in bell-state analysis

We demonstrate a new architecture for an optical entangling gate that is significantly simpler than previous realizations, using partially polarizing beam splitters so that only a single optical mode-matching condition is required. We demonstrate operation of a controlled-z gate in both continuous-wave and pulsed regimes of operation, fully characterizing it in each case using quantum process tomography. We also demonstrate a fully resolving, nondeterministic optical Bell-state analyzer based on this controlled-z gate. This new architecture is ideally suited to guided optics implementations of optical gates.     

Conceptual Design of a Dedicated Fourth-Generation Specialized Synchrotron Radiation Source (SSRS-4) at the Kurchatov Institute

Physics of Atomic Nuclei - Work on the conceptual design of a dedicated fourth-generation fourth-generation Specialized Synchrotron Radiation Source (SSRS-4) is in progress at the Kurchatov...     

Entanglement generation by Fock-state filtration

We demonstrate a Fock-state filter which is capable of preferentially blocking single photons over photon pairs. The large conditional nonlinearities are based on higher-order quantum interference, using linear optics, an ancilla photon, and measurement. We demonstrate that the filter acts coherently by using it to convert unentangled photon pairs to a path-entangled state. We quantify the degree of entanglement by transforming the path information to polarization information; applying quantum state tomography we measure a tangle of T=(20+/-9)%.     

Influence of scattering, atmospheric refraction, and ground effect on sound propagation through a pine forest

Sound propagation through a forest is affected by the microclimate in the canopy, scattering by trunks and stems, and ground reflection. Each of these effects is such a strong contributor to the attenuation of sound that mutual interactions between the phenomena could become important. A sound propagation model for use in a forest has been developed that incorporates scattering from trunks and branches and atmospheric refraction by modifying the effective wave number in the Green's function parabolic equation model. The ground effect for a hard-backed pine straw layer is approximated as a local reaction impedance condition. Comparisons to experimental data are made for frequencies up to 4,200 Hz. Cumulative influences of the separate phenomena are examined. The method developed in this paper is compared to previously published methods. The overall comparison with spectral transmission data is good, suggesting that the model captures the necessary details.     

Ultrafast intensity modulation by Raman gain for all-optical in-fiber processing

We present experimental results on ultrafast intensity modulation using the Raman effect and demonstrate 10-Gbit/s selective pulse erasure. The technique is both broadband and polarization insensitive and has a potential speed in excess of 500 Gbits/s. In addition to performing pulse erasure, this all-optical modulator can shape pulses as a precise, soft aperture scalpel and create short, dark pulses.