Scientific Commons: P. Postorino

High pressure behavior of Ga-doped LaMnO_3: a combined X-ray diffraction and optical spectroscopy study (2008)

Baldini, M., Malavasi, L., Di Castro, D., Nucara, A., Crichton, W., Mezouar, M., ...

The pressure effects on the JT distortion of three representative compounds belonging to the LaMn_1-xGa_xO_3 (x= 0.2, 0.3, 0.4) family was widely investigated by means of X-ray diffraction and Raman...

Evidence for coupling between collective state and phonons in two-dimensional charge-density-wave systems (2008)

Lavagnini, M., Baldini, M., Sacchetti, A., Di Castro, D., Delley, B., Monnier, R., ...

We report on a Raman scattering investigation of the charge-density-wave (CDW), quasi two-dimensional rare-earth tri-tellurides $R$Te$_3$ ($R$= La, Ce, Pr, Nd, Sm, Gd and Dy) at ambient pressure, and...

Probing the vortex state in CaC$_6$ using transverse field muon spin rotation (2008)

Kanigel, A., Di Castro, D., Keren, A., Postorino, P., Rosenmann, D., Welp, U., ...

We report temperature and transverse field-dependent muon spin relaxation measurements in a mosaic of single crystals of the superconductor CaC$_{6}$. The results indicate a fully gapped Fermi...

Pressure dependence of the optical properties of the charge-density-wave compound LaTe$_2$ (2007)

Lavagnini, M., Sacchetti, A., Degiorgi, L., Arcangeletti, E., Baldassarre, L., Postorino, P., ...

We report the pressure dependence of the optical response of LaTe$_2$, which is deep in the charge-density-wave (CDW) ground state even at 300 K. The reflectivity spectrum is collected in the...

High pressure Raman study of La$_{1-x}$Ca$_x$MnO$_{3-\delta}$ manganites (2007)

Sacchetti, A., Corridoni, T., Arcangeletti, E., Postorino, P.

We report on a high-pressure Raman study on two members of the La$_{1-x}$Ca$_x$MnO$_{3-\delta}$ manganite family ($x=0.20$, $\delta=0$ and $\delta=0.08$). The results obtained for the $\delta=0$...

Quasiparticle evolution and pseudogap formation in V2O3: An infrared spectroscopy study (2007)

Baldassarre, L., Perucchi, A., Nicoletti, D., Toschi, A., Sangiovanni, G., Held, K., ...

The infrared conductivity of V2O3 is measured in the whole phase diagram. Quasiparticles appear above the Neel temperature TN and eventually disappear further enhancing the temperature, leading to a...

Electrodynamics near the Metal-to-Insulator Transition in V3O5 (2007)

Baldassarre, L., Perucchi, A., Arcangeletti, E., Nicoletti, D., Di Castro, D., Postorino, P., ...

The electrodynamics near the metal-to-insulator transitions (MIT) induced, in V3O5 single crystals, by both temperature (T) and pressure (P) has been studied by infrared spectroscopy. The T- and...

Pressure and temperature dependence of the Fano resonance in the Raman spectrum of $A_2FeMoO_6$ systems (A=Sr,Ca) (2007)

Marrocchelli, D, Postorino, P, Di Castro, D, Arcangeletti, E, Dore, P, Guidi, Cestelli M

We report on Raman measurements carried out on $Ca_2FeMoO_6$ and $Sr_2FeMoO_6$ double perovskites as functions of pressure (0–15 GPa) and of temperature (298–370 K). The Raman spectrum of both...

Evidence of a pressure-induced metallization process in monoclinic VO$_2$ (2006)

Arcangeletti, E., Baldassarre, L., Di Castro, D., Lupi, S., Malavasi, L., Marini, C., ...

Raman and combined trasmission and reflectivity mid infrared measurements have been carried out on monoclinic VO$_2$ at room temperature over the 0-19 GPa and 0-14 GPa pressure ranges, respectively....

Pressure dependence of the charge-density-wave gap in rare-earth tri-tellurides (2006)

Sacchetti, A., Arcangeletti, E., Perucchi, A., Baldassarre, L., Postorino, P., Lupi, S., ...

We investigate the pressure dependence of the optical properties of CeTe$_3$, which exhibits an incommensurate charge-density-wave (CDW) state already at 300 K. Our data are collected in the...

Tuning topological disorder in MgB$_{2}$ (2006)

Di Castro, D., Cappelluti, E., Lavagnini, M., Sacchetti, A., Palenzona, A., Putti, M., ...

We carried out Raman measurements on neutron-irradiated and Al-doped MgB$_2$ samples. The irradiation-induced topological disorder causes an unexpected appearance of high frequency spectral...

Raman spectroscopy on cubic and hexagonal SrMnO$_3$ (2005)

Sacchetti, A., Baldini, M., Postorino, P., Martin, C., Maignan, A.

We report on the first optical characterization of both cubic and hexagonal SrMnO$_3$. Room-temperature Raman spectra collected by means of a micro-Raman spectrometer are shown. The spectrum of the...

Role of charge doping and lattice distortions in codoped Mg_{1-x}(AlLi)_{x}B_2 compounds (2005)

Monni, M., Ferdeghini, C., Manfrinetti, P., Palenzona, A., Putti, M., Affronte, M., ...

We prepared a series of Mg_{1-x}(AlLi)_{x}B_2 samples with 0≤x≤0.45 in order to compensate with Li the electron doping induced by Al. Structural characterization by means of neutron and...

Stabilization of an orthorhombic phase in LiMn2O4 by means of high pressure. (2005)

Paolone, A., Sacchetti, A., Postorino, P., Cantelli, R., Congeduti, A., Rousse, G., ...

LiMn2O4 is considered a promising material for the Li ion battery technology. Moreover, this material has been largely investigated in the last few years because it presents a charge order transition...

Clean and Dirty Superconductivity in Pure, Al doped, and Neutron Irradiated MgB2: a Far-Infrared Study (2004)

Ortolani, M., Di Castro, D., Postorino, P., Pallecchi, I., Monni, M., Putti, M., ...

The effects of Al substitution and neutron irradiation on the conduction regime (clean or dirty) of the $\pi$- and $\sigma$-band of MgB$_{2}$ have been investigated by means of far-infrared...

High-Pressure Phase Diagram in the Manganites: a Two-site Model Study (2004)

Sacchetti, A., Postorino, P., Capone, M.

The pressure dependence of the Curie temperature $T_C$ in manganites, recently studied over a wide pressure range, is not quantitatively accounted for by the quenching of Jahn-Teller distortions, and...

Pressure-tuning of the electron-phonon coupling: the insulator to metal transition in manganites (2003)

Postorino, P., Congeduti, A., Dore, P., Gorelli, F. A., Ulivi, L., Sacchetti, A., ...

A comprehensive understanding of the physical origin of the unique magnetic and transport properties of A_(1-x)A'^xMnO_3 manganites (A = trivalent rare-earth and A' = divalent alkali-earth metal) is...

Effect of Al doping on the optical phonon spectrum in Mg(1-x)Al(x)B(2) (2001)

Postorino, P., Congeduti, A., Dore, P., Nucara, A., Bianconi, A., Di Castro, D., ...

Raman and infrared absorption spectra of Mg(1-x)Al(x)B(2) have been collected for 0

Anomalous High Pressure Dependence of the Jahn-Teller Phonon in La0.75Ca0.25MnO3 (2001)

Congeduti, A, Postorino, P, Caramagno, E, Nardone, M, Kumar, A, Sarma, DD

Raman spectra of La0.75Ca0.25MnO3 have been collected for the first time over a wide pressure range 0 14 GPa using a diamond anvil cell. The frequency range explored 200 1100 cm21 and the very good...

Inelasticity effects in the neutron diffraction measurements from water steam using pulsed sources (1995)

Postorino, P, Nardone, M, Ricci, M A, Rovere, M

Neutron diffraction studies of H2O/D2O at supercritical temperatures: a direct determination of gHH(r),gOH(r) and gOO(r) (1994)

Tromp, R H, Postorino, P, Neilson, G W, Ricci, M A, Soper, A K

Water above its boiling point: study of the temperature and density dependence of the partial pair correlation functions. I - neutron diffraction experiment (1994)

Postorino, P, Ricci, M A, Soper, A K

Neutron diffraction study of heavy water steam (1994)

Buontempo, U, Postorino, P, Ricci, M A, Soper, A K

Radial distributions function of heavy water steam (1994)

Fontana, A, Postorino, P, Ricci, M A, Soper, A K

in Hydrogen Bond Networks, Eds M C Bellisent-Funel, J C Dore, Kluwer Academic Publishers, C345 69 (1994)

The interatomic structure of water at supercritical temperatures (1993)