Ikerbasque

About: Ikerbasque is a other organization based out in Bilbao, Spain. It is known for research contribution in the topics: Graphene & Quantum. The organization has 713 authors who have published 7967 publications receiving 231990 citations. The organization is also known as: Basque Foundation for Science.

Quantum simulation of the ultrastrong-coupling dynamics in circuit quantum electrodynamics

Abstract: . The authors acknowledge funding from the Juan de la Cierva MICINN Program, Spanish projects MICINN FIS2009-10061 and FIS2009-12773- C02-01; UPV/EHU UFI 11/55; QUITEMAD; the Basque Government IT472-10; SOLID, CCQED, and PROMISCE European projects; the SFB 631 of the Deutsche Forschungsgemeinschaft.

Solution processed polydimethylsiloxane/gold nanostar flexible substrates for plasmonic sensing

Abstract: Gold nanostars can display tunable optical properties in the visible and near IR, which lead to strong electromagnetic field enhancement at their tips. We report generalized application of gold nanostars for ultrasensitive identification of molecules, based on both localized surface plasmon resonance (LSPR) and surface enhanced Raman scattering (SERS). We address the requirements of plasmonic sensors, related to sufficiently large areas where nanoparticles are uniformly immobilized with high density, as well as mechanical flexibility, which offers additional advantages for real-world applications. Gold nanostar monolayers were thus immobilized on transparent, flexible polydimethylsiloxane substrates, and their refractive index sensitivity and SERS performance were studied. The application of such substrates for LSPR based molecular sensing is demonstrated via detection of a model analyte, mercaptoundecanoic acid. We further demonstrate SERS-based pesticide detection on fruit skin, by simply covering the fruit surface with the flexible plasmonic substrate, at the area where the target molecule is to be detected. The transparency of the substrate allows SERS detection through backside excitation, thereby facilitating practical implementation.

Hydrogen and halogen bonds are ruled by the same mechanisms.

Abstract: Hydrogen and halogen bonds are compared on the basis of ab initio calculations performed for complexes linked through these interactions. The Quantum Theory of Atoms in Molecules (QTAIM) and the Natural Bond Orbitals (NBO) method are applied for a deeper understanding of the nature of interactions. Both interactions are ruled by the same effects of hyperconjugation and rehybridization. In general for both kinds of interactions the same processes of the electron charge redistribution being the result of complexation are observed. As a consequence similar characteristics are also observed for the hydrogen and halogen bonds for example the increase of the positive charge of the atom being in contact with the Lewis base (hydrogen and chlorine or bromine for complexes analyzed here) and the decrease of its volume as a result of the complex formation. The halogen bond is enhanced by the charge assistance, similarly to the hydrogen bond.

Study of exclusive B→Xuℓν decays and extraction of |Vub| using full reconstruction tagging at the Belle experiment

Abstract: We report the results of a study of the exclusive semileptonic decays ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}}$, ${\overline{B}}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}}$, ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}}$, ${\overline{B}}^{0}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}}$ and ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\omega}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}}$, where $\ensuremath{\ell}$ represents an electron or a muon. The events are tagged by fully reconstructing a second $B$ meson in the event in a hadronic decay mode. The measured branching fractions are $\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}})=(0.80\ifmmode\pm\else\textpm\fi{}0.08\ifmmode\pm\else\textpm\fi{}0.04)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}})=(1.49\ifmmode\pm\else\textpm\fi{}0.09\ifmmode\pm\else\textpm\fi{}0.07)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, $\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{0}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}})=(1.83\ifmmode\pm\else\textpm\fi{}0.10\ifmmode\pm\else\textpm\fi{}0.10)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, $\mathcal{B}({\overline{B}}^{0}\ensuremath{\rightarrow}{\ensuremath{\rho}}^{+}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}})=(3.22\ifmmode\pm\else\textpm\fi{}0.27\ifmmode\pm\else\textpm\fi{}0.24)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, and $\mathcal{B}({B}^{\ensuremath{-}}\ensuremath{\rightarrow}\ensuremath{\omega}{\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}})=(1.07\ifmmode\pm\else\textpm\fi{}0.16\ifmmode\pm\else\textpm\fi{}0.07)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$, where the first error is statistical and the second one is systematic. The obtained branching fractions are inclusive of soft photon emission. We also determine the branching fractions as a function of the 4-momentum transfer squared to the leptonic system ${q}^{2}=({p}_{\ensuremath{\ell}}+{p}_{\ensuremath{ u}}{)}^{2}$, where ${p}_{\ensuremath{\ell}}$ and ${p}_{\ensuremath{ u}}$ are the lepton and neutrino 4-momenta, respectively. Using the pion modes, a recent light cone sum rule calculation, lattice QCD results and a model-independent description of the hadronic form factor, a value of the Cabibbo-Kobayashi-Maskawa matrix element $|{V}_{ub}|=(3.52\ifmmode\pm\else\textpm\fi{}0.29)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}3}$ is extracted. A structure in the two-pion invariant mass distribution near $1.3\text{ }\text{ }\mathrm{GeV}/{c}^{2}$, which might be dominated by the decay ${B}^{\ensuremath{-}}\ensuremath{\rightarrow}{f}_{2}(1270){\ensuremath{\ell}}^{\ensuremath{-}}{\overline{\ensuremath{ u}}}_{\ensuremath{\ell}}$, ${f}_{2}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{\ensuremath{-}}$, is seen. These results are obtained from a $711\text{ }\text{ }{\mathrm{fb}}^{\ensuremath{-}1}$ data sample that contains $772\ifmmode\times\else\texttimes\fi{}{10}^{6}$ $B\overline{B}$ pairs, collected near the $\ensuremath{\Upsilon}(4S)$ resonance with the Belle detector at the KEKB asymmetric-energy ${e}^{+}{e}^{\ensuremath{-}}$ collider.