Zobrazeno 1 - 10
of 450
pro vyhledávání: '"Tropeano M."'
Autor:
Daghero, D., Tortello, M., Ummarino, G. A., Stepanov, V. A., Bernardini, F., Tropeano, M., Putti, M., Gonnelli, R. S.
Publikováno v:
Supercond. Sci. Technol. 25, 084012 (2012)
We studied the effects of isoelectronic Ru substitution at the Fe site on the energy gaps of optimally F-doped SmFeAsO by means of point-contact Andreev reflection spectroscopy. The results show that the SmFe_{1-x}Ru_{x}AsO_{0.85}F_{0.15} system keep
Externí odkaz:
http://arxiv.org/abs/1301.3757
Autor:
Prando, G., Sanna, S., Lamura, G., Shiroka, T., Tropeano, M., Palenzona, A., Grafe, H. -J., Büchner, B., Carretta, P., De Renzi, R.
Publikováno v:
Phys. Status Solidi B 250, 599 (2013)
In this paper we report a detailed $\mu^{+}$SR and {}$^{19}$F-NMR study of the La$_{0.7}$Y$_{0.3}$FeAsO$_{1-x}$F$_{x}$ class of materials. Here, the diamagnetic La$_{1-y}$Y$_{y}$ substitution increases chemical pressure and, accordingly, sizeably enh
Externí odkaz:
http://arxiv.org/abs/1209.6512
Autor:
Palenzona, A., Sala, A., Bernini, C., Braccini, V., Cimberle, M. R., Ferdeghini, C., Lamura, G., Martinelli, A., Pallecchi, I., Romano, G., Tropeano, M., Fittipaldi, R., Vecchione, A., Polyanskii, A., Kametani, F., Putti, M.
Publikováno v:
Supercond. Sci. Technol. 25 115018 2012
A novel method to prepare bulk Fe(Se0.5Te0.5) samples is presented, based on a melting process and a subsequent annealing treatment. With respect to the standard sintering technique, it produces much more homogeneous and denser samples, characterized
Externí odkaz:
http://arxiv.org/abs/1205.3618
Autor:
Shiroka, T., Lamura, G., Sanna, S., Prando, G., De Renzi, R., Tropeano, M., Cimberle, M. R., Martinelli, A., Bernini, C., Palenzona, A., Fittipaldi, R., Vecchione, A., Carretta, P., Siri, A. S., Ferdeghini, C., Putti, M.
The evolution of the antiferromagnetic order parameter in CeFeAsO_{1-x}F_{x} as a function of the fluorine content x was investigated primarily via zero-field muon-spin spectroscopy. The long-range magnetic order observed in the undoped compound grad
Externí odkaz:
http://arxiv.org/abs/1109.3170
Autor:
Pallecchi, I., Bernardini, F., Tropeano, M., Palenzona, A., Martinelli, A., Ferdeghini, C., Vignolo, M., Massidda, S., Putti, M.
Publikováno v:
Physical Review B 84, 134524 (2011)
In this work we investigate the Ru substituted LaFeAsO compound, by studying the magnetotransport behaviour and its relationship with the band structure, in different regimes of temperature, magnetic field and Ru content. In particular we analyse the
Externí odkaz:
http://arxiv.org/abs/1106.3973
Publikováno v:
Phys. Rev. B 84, 064507 (2011)
Superconducting fluctuations (SF) in SmFeAsO$_{0.8}$F$_{0.2}$ (characterized by superconducting transition temperature $T_{c} \simeq 52.3$ K) are investigated by means of isothermal high-resolution dc magnetization measurements. The diamagnetic respo
Externí odkaz:
http://arxiv.org/abs/1104.1312
Publikováno v:
Phys. Rev. B 83, 174514 (2011)
Ac susceptibility and static magnetization measurements were performed in the optimally doped SmFeAsO$_{0.8}$F$_{0.2}$ superconductor. The field - temperature phase diagram of the superconducting state was drawn and, in particular, the features of th
Externí odkaz:
http://arxiv.org/abs/1102.1404
Autor:
Vajpayee, Arpita, Jha, R., Srivastava, A. K., Kishan, H., Tropeano, M., Ferdeghini, C., Awana, V. P. S.
Publikováno v:
Sup. Sci. & Tech. 24, 045013 (2011)
We study the effect of synthesis temperature on the phase formation in nano(n)-SiC added bulk MgB2 superconductor. In particular we study: lattice parameters, amount of carbon (C) substitution, microstructure, critical temperature (Tc), irreversibili
Externí odkaz:
http://arxiv.org/abs/1101.5206
Autor:
Yamamoto, A., Jiang, J., Kametani, F., Polyanskii, A., Hellstrom, E., Larbalestier, D., Martinelli, A., Palenzona, A., Tropeano, M., Putti, M.
Publikováno v:
Supercond. Sci. Technol. 24, 045010 (2011)
We prepared polycrystalline SmFeAsO1-xFx (Sm1111) bulk samples by sintering and hot isostatic pressing (HIP) in order to study the effects of phase purity and relative density on the intergranular current density. Sintered and HIPped Sm1111 samples a
Externí odkaz:
http://arxiv.org/abs/1011.2547
Publikováno v:
J. Appl. Phys. 109, 07E121 (2011)
We synthesized bulk polycrystalline samples of RECoAsO (RE=La, Nd and Sm) by solid state reaction route in an evacuated sealed quartz tube. All these compounds are crystallized in a tetragonal structure with space group P4/nmm. The Co, in these compo
Externí odkaz:
http://arxiv.org/abs/1008.4999