BT Literature Database -- Query Results

Abstract: A recent investigation of the low temperature properties of the paramagnetic heavy fermion system CeRuSi revealed an anomalous decrease of the coefficient C/T below 6 K, indicating a second low energy scale well below the Kondo temperature of about 50 K. We started an investigation of this unusual behavior using the local probe ²⁹Si-NMR. Here a preliminary ²⁹Si field sweep NMR study in the temperature 4.2-200 K is reported. ²⁹Si-NMR powder spectra obtained at 72.9 MHz could be simulated and shift components ²⁹K_ab(T) and ²⁹K _c(T) were determined. The shift along the basal plane ²⁹K_ab(T) shows the expected behavior with a Curie-Weiss dependence at high T merging in a constant value below 15 K. In contrast the shift along the tetragonal axis reveals an anomalous T dependence below 15 K where ²⁹K_c(T) drops by a factor of 2, confirming the presence of a further low T energy scale. We suspect this drop to be related to the anomalous decrease of C/T below 6 K and discuss possible mechanism. Â© 2010 IOP Publishing Ltd.

Keywords: Basal planes; Energy scale; Heavy fermion systems; High-T; Kondo temperatures; Local probes; Low energies; NMR studies; Powder spectra; Drops; Silicon

Permanent link

| Save citation: RTF PDF LaTeX

| Export record: BibTeX Endnote ISI RIS Atom XML MODS XML ODF XML Word XML

Abstract: The hysteretic magnetic flux dynamics of ceramic type-II superconductors under superimposed transport current cycles has been investigated. Field cooled and zero field cooled experiments were carried-out on polycrystalline YBa 2Cu3O7-x cylinders by using both temperature and applied field control, to drive the sample into the semi-reversible granular regime. The transport current magnitude was near and above the dissipative threshold. The interplay between shielding and transport due to vortex-pinning interactions, equilibrium magnetization effects, and diamagnetic/paramagnetic relaxation phenomena are shown to play an important role in the range of practical applications.

	BT Literature Database Home \| Show All \| Simple Search \| Advanced Search	Login Quick Search: Field: contains: ...
	1-2 of 2 records found matching your query:

	Sarkar, R., M. Baenitz, J. G. Sereni, and C. Geibel. "²⁹Si NMR study of the heavy fermion system CeRuSi." Journal of Physics: Conference Series 200 (2010): 012173. Abstract: A recent investigation of the low temperature properties of the paramagnetic heavy fermion system CeRuSi revealed an anomalous decrease of the coefficient C/T below 6 K, indicating a second low energy scale well below the Kondo temperature of about 50 K. We started an investigation of this unusual behavior using the local probe ²⁹Si-NMR. Here a preliminary ²⁹Si field sweep NMR study in the temperature 4.2-200 K is reported. ²⁹Si-NMR powder spectra obtained at 72.9 MHz could be simulated and shift components ²⁹K_ab(T) and ²⁹K _c(T) were determined. The shift along the basal plane ²⁹K_ab(T) shows the expected behavior with a Curie-Weiss dependence at high T merging in a constant value below 15 K. In contrast the shift along the tetragonal axis reveals an anomalous T dependence below 15 K where ²⁹K_c(T) drops by a factor of 2, confirming the presence of a further low T energy scale. We suspect this drop to be related to the anomalous decrease of C/T below 6 K and discuss possible mechanism. Â© 2010 IOP Publishing Ltd. Keywords: Basal planes; Energy scale; Heavy fermion systems; High-T; Kondo temperatures; Local probes; Low energies; NMR studies; Powder spectra; Drops; Silicon Permanent link \| Save citation: RTF PDF LaTeX \| Export record: BibTeX Endnote ISI RIS Atom XML MODS XML ODF XML Word XML
	Giordano, J. L., J. Luzuriaga, Ruíz-Tagle, G. NIEVA, and Badía-Majós. "Magnetization measurements of hard superconductors under dissipative transport." Journal of Physics: Conference Series 43, no. 1 (2006): 663–666. Abstract: The hysteretic magnetic flux dynamics of ceramic type-II superconductors under superimposed transport current cycles has been investigated. Field cooled and zero field cooled experiments were carried-out on polycrystalline YBa 2Cu3O7-x cylinders by using both temperature and applied field control, to drive the sample into the semi-reversible granular regime. The transport current magnitude was near and above the dissipative threshold. The interplay between shielding and transport due to vortex-pinning interactions, equilibrium magnetization effects, and diamagnetic/paramagnetic relaxation phenomena are shown to play an important role in the range of practical applications. Permanent link \| Save citation: RTF PDF LaTeX \| Export record: BibTeX Endnote ISI RIS Atom XML MODS XML ODF XML Word XML