763 research outputs found
Experimental demonstration of entanglement assisted coding using a two-mode squeezed vacuum state
We have experimentally realized the scheme initially proposed as quantum
dense coding with continuous variables [Ban, J. Opt. B \textbf{1}, L9 (1999),
and Braunstein and Kimble, \pra\textbf{61}, 042302 (2000)]. In our experiment,
a pair of EPR (Einstein-Podolski-Rosen) beams is generated from two independent
squeezed vacua. After adding two-quadrature signal to one of the EPR beams, two
squeezed beams that contain the signal were recovered. Although our squeezing
level is not sufficient to demonstrate the channel capacity gain over the
Holevo limit of a single-mode channel without entanglement, our channel is
superior to conventional channels such as coherent and squeezing channels. In
addition, optical addition and subtraction processes demonstrated are
elementary operations of universal quantum information processing on continuous
variables.Comment: 4 pages, 4 figures, submitted to Phys. Rev.
Visible-light-assisted selective catalytic reduction of NO with NH[3] on porphyrin derivative-modified TiO[2] photocatalysts
Accepted 16 Sep 2014.Porphyrin-derivative-modified TiO[2] photocatalysts showed high photocatalytic activity for the selective catalytic reduction of NO with NH[3] in the presence of O[2] under visible-light irradiation. Tetra(p-carboxyphenyl)porphyrin (TCPP) was the most effective photosensitizer among the five porphyrin derivatives investigated. NO conversion and N[2] selectivity of 79.0% and 100%, respectively, were achieved at a gas hourly space velocity of 50 000 h[−1]. UV–Vis and photoluminescence spectroscopies revealed the presence of two species of TCPP on the TiO2surface; one was a TCPP monomer and the other was an H-aggregate of the TCPP molecules. It was concluded that the TCPP monomer is an active species for the photo-assisted selective catalytic reduction (photo-SCR). Moreover, an increase in the fraction of H-aggregates with increasing TCPP loading amount resulted in a decrease in the photocatalytic activity of the photo-SCR
Extension of measurement range in OCDR based on double-modulation scheme
We extend the measurement range of optical correlation-domain reflectometry
(OCDR) by modulating the laser output frequency at two frequencies, while
preserving spatial resolution. We demonstrate distributed reflectivity sensing
with a ten-fold extended measurement range.Comment: 4 pages, 6 figure
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