45,366 research outputs found
Grover's search algorithm: An optical approach
The essential operations of a quantum computer can be accomplished using
solely optical elements, with different polarization or spatial modes
representing the individual qubits. We present a simple all-optical
implementation of Grover's algorithm for efficient searching, in which a
database of four elements is searched with a single query. By `compiling' the
actual setup, we have reduced the required number of optical elements from 24
to only 12. We discuss the extension to larger databases, and the limitations
of these techniques.Comment: 6 pages, 5 figures. To appear in a special issue of the Journal of
Modern Optics -- "The Physics of Quantum Information
Quantitative analysis of TM lateral leakage in foundry fabricated silicon Rib waveguides
We show that thin, shallow ridge, silicon-on-insulator waveguides exhibiting a lateral leakage behavior can be designed and fabricated using a standard silicon photonic foundry platform. We analyze the propagation loss through the observation of the transmitted TM polarized guided mode and TE polarized radiation and experimentally demonstrate that propagation losses as low as 0.087 dB/mm can be achieved. This demonstration will open a new frontier for practical devices exploiting a lateral leakage behavior with potential applications in the fields of biosensing and quantum optics among others
Microstructure and mechanical properties of bulk yttria-partially-stabilized zirconia
A commercially available bulk 4.5 mole percent yttria-(Y2O3) partially stabilized zirconia (PSZ) was studied by light microscopy, X-ray analysis, microhardness measurement, and fracture toughness testing. The growth of the precipitates and the phase transformations were studied as a function of aging in air at 1500 C. Aging curves were constructed for both the as received and the solution annealed and quenched materials; the curves showed hardness peaks at 1397 and 1517 Kg/sq mm respectively. The rectangular plate shaped tetragonal precipitates were found to have a 110 habit plane. A total of twelve different types of tetragonal precipitates were found. Grinding of the Y2O3 PSZ into powder did not cause a significant amount of metastable tetragonal precipitates to transform into the monoclinc phase, thus indicating that transformation toughening is not a significant mechanism for the material
Thirteen-color narrow-band photometry of one thousand bright stars
Thirteen-color narrow-band photometry of one thousand bright star
Aerodynamic data on a large semispan tilting wing with 0.5-diameter chord, double-slotted flap, and both left-hand and right-hand rotation of a single propeller
Longitudinal aerodynamic data on large-scale semispan V/STOL tilt-wing configuration having single propeller with left and right hand rotatio
Long-range Ni/Mn structural order in epitaxial double perovskite La2NiMnO6 thin films
We report and compare the structural, magnetic, and optical properties of
ordered La2NiMnO6 thin films and its disordered LaNi0.5Mn0.5O3 counterpart. An
x-ray diffraction study reveals that the B-site Ni/Mn ordering induces
additional XRD reflections as the crystal symmetry is transformed from a
pseudocubic perovskite unit cell in the disordered phase to a monoclinic form
with larger lattice parameters for the ordered phase. Polarized Raman
spectroscopy studies reveal that the ordered samples are characterized by
additional phonon excitations that are absent in the disordered phase. The
appearance of these additional phonon excitations is interpreted as the
clearest signature of Brillouin zone folding as a result of the long-range
Ni/Mn ordering in La2NiMnO6. Both ordered and disordered materials display a
single ferromagnetic-to-paramagnetic transition. The ordered films display also
a saturation magnetization close to 4.8 mB/f.u. and a transition temperature
(FM-TC) around 270 K, while the disordered ones have only a 3.7 mB/f.u.
saturation magnetization and a FM-TC around 138 K. The differences in their
magnetic behaviours are understood based on the distinct local electronic
configurations of their Ni/Mn cations.Comment: 15 pages, 5 fig
Phase formation, phonon behavior, and magnetic properties of novel ferromagnetic La3BAlMnO9 (B = Co or Ni) triple perovskites
In the quest for novel magnetoelectric materials, we have grown, stabilized
and explored the properties of La3BAlMnO9 (B = Co or Mn) thin films. In this
paper, we report the influence of the growth parameters that promote B/Al/Mn
ordering in the pseudo-cubic unit cell and their likely influence on the
magnetic and multiferroic properties. The temperature dependence of the
magnetization shows that La3CoAlMnO9 is ferromagnetic up to 190 K while
La3NiAlMnO9 shows a TC of 130 K. The behavior of these films are compared and
contrasted with related La2BMnO6 double perovskites. It is observed that the
insertion of AlO6 octahedra between CoO6 and MnO6 suppresses significantly the
strength of the superexchange interaction, spin-phonon and spin-polar coupling.Comment: 13 pages, 3 fig
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