0000000000400695
AUTHOR
Massimo Piccinini
Optical, infrared and electron-microscopy studies of metallic clusters in layered crystals
Abstract An influence of ( Cd i ) n metallic clusters on the optical absorption and phonon spectra of CdI 2 crystals was studied. Metallic clusters of spherical shape were formed during the growth of non-stoichiometric crystals. Radii of clusters are in range from 10 to 500 nm according to scanning electron microscopy (SEM) data. The density of clusters was estimated from fractal dimension calculations. The fractal dimension of ( Cd i ) n clusters has been found to be varied from 1.488 to 1.793. In the framework of Mie theory the spectral and size dependencies of extinction coefficients were calculated. From the experimentally obtained spectra it is evident that the metallic clusters are re…
Influence of diamagnetic impurity on mid‐IR absorption in antiferromagnetic insulator NiO
-1 was studied in polycrystalline Ni c Mg 1-c O solid solutions with c=0.99, 0.98, 0.97, 0.95, 0.90, 0.80, 0.70 and 0.60. The composition and temperature dependences of the absorption suggest that the band has magnetic origin re- lated to simultaneous excitation of two-magnons at the Brillouin-zone boundary and one phonon. -1 in polycrystalline NicMg1-cO solid solutions. Polycrystalline solid solutions NicMg1-cO (c=0.99, 0.98, 0.97, 0.95, 0.90, 0.80, 0.70 and 0.60) were prepared using ceramic technology from the appropriate amounts of aqueous solutions of Mg(NO3)2·6H2O and Ni(NO3)2·6H2O salts, which were mixed and slowly evaporated. The remaining dry 'flakes' were heated up to 500-600 oC to…
Measurements of the Nuclear Modification Factor for Jets inPb+PbCollisions atsNN=2.76 TeVwith the ATLAS Detector
Measurements of inclusive jet production are performed in pp and Pb+Pb collisions at √sNN = 2.76 TeV with the ATLAS detector at the LHC, corresponding to integrated luminosities of 4.0 pb−1 and 0.14 nb−1, respectively. The jets are identified with the anti-kt algorithm with R = 0.4, and the spectra are measured over the kinematic range of jet transverse momentum 32 < pT < 500 GeV, and absolute rapidity |y| < 2.1 and as a function of collision centrality. The nuclear modification factor, RAA, is evaluated and jets are found to be suppressed by approximately a factor of two in central collisions compared to pp collisions. The RAA shows a slight increase with pT and no significant variation wi…
CsPbCl3 nanocrystals dispersed in the Rb0,8Cs0,2Cl matrix studied by far-infrared spectroscopy
Abstract The comparative far-infrared spectroscopy studies of Rb0.8Cs0.2Cl and Rb0.8Cs0.2Cl containing CsPbCl3 nanocrystals between 170 and 320 K are reported. The effect of cesium lead chloride nanocrystals on the phonon modes of the host matrix, particularly manifested in different temperature behavior of LO–TO splitting and the temperature dependence of high frequency dielectric constant, are demonstrated.