Jožef Stefan Institute

About: Jožef Stefan Institute is a facility organization based out in Ljubljana, Slovenia. It is known for research contribution in the topics: Liquid crystal & Dielectric. The organization has 3828 authors who have published 12614 publications receiving 291025 citations.

Processing and Dielectric Properties of Sillenite Compounds Bi12MO20−δ (M = Si, Ge, Ti, Pb, Mn, B1/2P1/2)

Abstract: Six sillenite compounds Bi12MO20-δ (M = Si, Ge, Ti, Pb, Mn, B1/2P1/2) were synthesized, and the resulting single-phase powders were then sintered to obtain ∼97% dense ceramics. An analysis of their microwave dielectric properties, performed at ∼5.5 GHz, revealed a permittivity of ∼40 for all six compounds. The temperature coefficient of resonant frequency was the lowest for the Pb analogue (−84 ppm/K) and was found to increase with increasing ionic radius of the B-site ion to a value of −20 ppm/K for the Bi12SiO20 and Bi12(B1/2P1/2)O20 compounds. The Q×f value is a maximum for Bi12SiO20 and Bi12GeO20 with 8100 and 7800 GHz, respectively. The dielectric properties of the sillenites have been correlated with the structure of the oxygen network of the sillenite crystal lattice. As a result of its low sintering temperature (850°C), chemical compatibility with silver, low dielectric losses, and temperature-stable permittivity, the Bi12SiO20 compound is a suitable material for applications in low-temperature cofiring ceramic (LTCC) technology.

Dsmesons withDKandD*Kscattering near threshold

Abstract: ${D}_{s}$ mesons are studied in three quantum channels (${J}^{P}={0}^{+}$, ${1}^{+}$ and ${2}^{+}$), where experiments have identified the very narrow ${D}_{s0}^{*}(2317)$, ${D}_{s1}(2460)$ and narrow ${D}_{s1}(2536)$, ${D}_{s2}^{*}(2573)$. We explore the effect of nearby $DK$ and ${D}^{*}K$ thresholds on the subthreshold states using lattice QCD. Our simulation is done on two very different ensembles of gauge configurations (2 or $2+1$ dynamical quarks, Pion mass of 266 or 156 MeV, lattice size $1{6}^{3}\ifmmode\times\else\texttimes\fi{}32$ or $3{2}^{3}\ifmmode\times\else\texttimes\fi{}64$). In addition to $\overline{q}q$ operators we also include meson-meson interpolators in the correlation functions. This clarifies the identification of the states above and below the scattering thresholds. The ensemble with ${m}_{\ensuremath{\pi}}\ensuremath{\simeq}156\text{ }\text{ }\mathrm{MeV}$ renders the ${D}_{s1}(2460)$ as a strong interaction bound state 44(10) MeV below ${D}^{*}K$ threshold, which is in agreement with the experiment. The ${D}_{s0}^{*}(2317)$ is found 37(17) MeV below $DK$ threshold, close to the experiment value of 45 MeV. The narrow resonances ${D}_{s1}(2536)$ and ${D}_{s2}^{*}(2573)$ are also found close to the experimental masses.

DFT Study of Interaction of Azoles with Cu(111) and Al(111) Surfaces: Role of Azole Nitrogen Atoms and Dipole–Dipole Interactions

Abstract: Azoles and their derivatives are among the often used organic corrosion inhibitors for copper. For this reason, the adsorption of four azole molecules—imidazole, 1,2,3-triazole, tetrazole, and pent...

Coupled channel analysis of the rho meson decay in lattice QCD

Abstract: We employ a variational basis with a number of $\overline{q}q$ and $\ensuremath{\pi}\ensuremath{\pi}$ lattice interpolating fields with quantum numbers of the $\ensuremath{\rho}$ resonance to extract the discrete energy spectrum in a finite volume. In the elastic region, this spectrum is related to the phase shift of the continuum scattering amplitude by L\"uscher's formula, and the relation allows the extraction of resonance parameters from the spectrum calculation. The simulations are performed at three different total momenta of the coupled $\overline{q}q\ensuremath{-}\ensuremath{\pi}\ensuremath{\pi}$ system, which allows us to extract the $p$-wave scattering phase at five values of pion relative momenta near the resonance region. The effective range formula describes the phase-shift dependence nicely, and we extract the resonance mass ${m}_{\ensuremath{\rho}}=792(7)(8)\text{ }\text{ }\mathrm{MeV}$ and the coupling ${g}_{\ensuremath{\rho}\ensuremath{\pi}\ensuremath{\pi}}=5.13(20)$ at our ${m}_{\ensuremath{\pi}}\ensuremath{\simeq}266\text{ }\text{ }\mathrm{MeV}$. The coupling ${g}_{\ensuremath{\rho}\ensuremath{\pi}\ensuremath{\pi}}$ is directly related to the width of the $\ensuremath{\rho}$ meson, and our value is close to the value derived from the experimental width. The simulations are performed using dynamical gauge configurations with two mass-degenerate flavors of tree-level improved clover-Wilson fermions. Correlation functions are calculated using the recently proposed distillation method with Laplacian-Heaviside smearing of quarks, which enables flexible calculations, in many cases with unprecedented accuracy.