3,435 research outputs found
Experimental high-intensity three-photon entangled source
We experimentally realize a high-intensity three-photon
Greenberger-Horne-Zeilinger (GHZ) entanglement source directly following the
proposal by Rarity and Tapster [J. G. Rarity and P. R. Tapster, Phys. Rev. A
59, R35 (1999)]. The threefold coincidence rate can be more than 200 Hz with a
fidelity of 0.811, and the intensity can be further improved with moderate
fidelity degradation. The GHZ entanglement is characterized by testing the
Bell-Mermin inequality and using an entanglement witness operator. To optimize
the polarization-entangled source, we theoretically analyze the relationship
between the mean photon number of the single-photon source and the probability
of parametric down-conversion.Comment: 4 pages, 4 figure
Efficient parameter inference for gravitational wave signals in the presence of transient noises using temporal and time-spectral fusion normalizing flow
Glitches represent a category of non-Gaussian and transient noise that
frequently intersects with gravitational wave (GW) signals, exerting a notable
impact on the processing of GW data. The inference of GW parameters, crucial
for GW astronomy research, is particularly susceptible to such interference. In
this study, we pioneer the utilization of temporal and time-spectral fusion
normalizing flow for likelihood-free inference of GW parameters, seamlessly
integrating the high temporal resolution of the time domain with the frequency
separation characteristics of both time and frequency domains. Remarkably, our
findings indicate that the accuracy of this inference method is comparable to
traditional non-glitch sampling techniques. Furthermore, our approach exhibits
greater efficiency, boasting processing times on the order of milliseconds. In
conclusion, the application of normalizing flow emerges as pivotal in handling
GW signals affected by transient noises, offering a promising avenue for
enhancing the field of GW astronomy research.Comment: 13 pages, 10 figure
catena-Poly[[[aquasilver(I)]-μ-4,4′-bipyridine-κ2 N:N′] 4-aminobenzoate nitrate hydrate]
In the structure of the title compound, 2[Ag(C10H8N2)(H2O)](C7H6NO2)(NO3)·H2O, the AgI atom is three-coordinated in a T-shaped configuration by two N atoms from two symmetry-related 4,4′-bipyridine (bipy) ligands at short distances and by one water O atom at a longer distance. Each bipy ligand bridges two neighbouring AgI atoms, forming a chain structure extending parallel to [101]. The complete 4-aminobenzoate anion, the nitrate anion and the uncoordinated water molecule are located on mirror planes: together with the coordinated water molecule, they form N—H⋯O, O—H⋯O and O—H⋯N hydrogen bonds, stabilizing the crystal structure
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