|   | 
Details
   web
Records
Author Sarkar, R.; Baenitz, M.; Sereni, J.G.; Geibel, C.
Title 29Si NMR study of the heavy fermion system CeRuSi Type Journal Article
Year 2010 Publication Journal of Physics: Conference Series Abbreviated Journal (up) J. Phys. Conf. Ser.
Volume 200 Issue Pages 012173
Keywords Basal planes; Energy scale; Heavy fermion systems; High-T; Kondo temperatures; Local probes; Low energies; NMR studies; Powder spectra; Drops; Silicon
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 29Kab(T) and 29K c(T) were determined. The shift along the basal plane 29Kab(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 29Kc(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. © 2010 IOP Publishing Ltd.
Address Divisin Bajas Temperaturas, Centro Atmico Bariloche, Comisin Nacional de Energia Atmica, cc 439, 8400 San Carlos de Bariloche, Argentina
Corporate Author Thesis
Publisher Place of Publication Karlsruhe Editor
Language Summary Language Original Title
Series Editor Series Title International Conference on Magnetism, ICM 2009 Abbreviated Series Title
Series Volume 200 Series Issue SECTION 1 Edition
ISSN 17426588 (ISSN) ISBN Medium
Area Expedition Conference
Notes Conference code: 81773; Export Date: 10 December 2010; Source: Scopus; Art. No.: 012173; doi: 10.1088/1742-6596/200/1/012173; Language of Original Document: English; Correspondence Address: Sarkar, R.; Max-Planck Institute for Chemical Physics of Solids, 01187 Dresden, Germany; email: rajibsarkarsinp@gmail.com; References: Sereni, J.G., J. Phys.: Condens. Matter., , submitted to; Welter, R., (1992) J. Alloys Comput., 189 (1), p. 49; Chevalier, B., (2008) Phys. Rev., 77 (1), p. 014414; Rebelsky, L., (1988) J. Appl.Phys., 63 (8), p. 3405; Kitaoka, Y., (1985) J. Phys. Soc. Japan., 54 (9), p. 3236; Krishna-Murthy, H.R., (1975) Phys. Rev. Lett., 35 (16), p. 1101; Chevalier, B., (2006) Physica, 378-380, p. 795; Kim, J.K., Troyer, M., (1998) Phys. Rev. Letter, 80 (12), p. 2705 Approved no
Call Number BT @ berisso @ Serial 598
Permanent link to this record
 

 
Author Deppe, M.; Caroca-Canales, N.; Sereni, J.G.; Geibel, C.
Title Evidence for a metamagnetic transition in the heavy Fermion system CeTiGe Type Conference Article
Year 2010 Publication Journal of Physics: Conference Series Abbreviated Journal (up) J. Phys.: Conf. Ser.
Volume 200 Issue Pages 012026
Keywords Applied magnetic fields; Canonical systems; Continuous suppression; Critical behavior; Critical fields; DC magnetization; First order; Heavy fermion systems; Higher temperatures; Low temperatures; Metamagnetic; Metamagnetic transitions; Polycrystalline; Cerium; Cerium compounds; Electric resistance; Magnetic field effects; Magnetoresistance; Magnetism
Abstract A recent study of CeTiGe identified this compound as a paramagnetic heavy Fermion system where the full J = 5/2 multiplet is involved in the formation of the ground state. Here we present a preliminary investigation of the dc-magnetization Mdc(H) and of the magnetoresistance ρ(H) of polycrystalline CeTiGe samples in applied magnetic fields up to μ0H = 14 T. The results reveal a pronounced metamagnetic transition at a critical field μ0Hc ≈ 13.5 T at low temperatures, with a step like increase in Mdc(H) of at least 0.6 μB/Ce. The metamagnetic transition leads to a strong decrease in ρ(H). A clear hysteresis in Mdc(H) and ρ(H) indicate that in CeTiGe these metamagnetic features correspond to a true thermodynamic, first order type transition in contrast to the critical behavior observed in the canonical system CeRu2Si2. Measurements at higher temperatures showed a continuous suppression of the metamagnetic transition with increasing T, which vanishes at T ∼ 30 K. © 2010 IOP Publishing Ltd.
Address
Corporate Author Thesis
Publisher Place of Publication Karlsruhe Editor
Language Summary Language Original Title
Series Editor Series Title International Conference on Magnetism, ICM 2009 Abbreviated Series Title
Series Volume 200 Series Issue SECTION 1 Edition
ISSN 17426588 (ISSN) ISBN Medium
Area Expedition Conference
Notes Conference code: 81773; Export Date: 10 December 2010; Source: Scopus; Art. No.: 012026; doi: 10.1088/1742-6596/200/1/012026; Language of Original Document: English; Correspondence Address: Deppe, M.; Max Planck Institute for Chemical Physics of Solids, D-01187 Dresden, Germany; email: Hicha.Deppe@cpfs.mpg.de; References: Gegenwart, P., Si, Q., Steglich, F., (2008) Nature Phys., 4 (3), p. 186; Sachdev, S., (2008) Nature Phys., 4 (3), p. 173; Blundell, S., (2001) Oxford Master Series in Condensed Matter Physics, , (Oxford University Press); Monthoux, P., Lonzarich, G.G., (2001) Phys. Rev., 63 (5), p. 054529; Morozkin, A.V., Seropegin Yu, D., Leonov, A.V., Sviridov, I.A., Tskhadadze, I.A., Nikitin, S.A., (1998) J. Alloys Comput., 267, pp. 14-15R; Welter, R., Vernière, A., Venturini, G., Malaman, B., (1999) J. Alloys. Compounds, 283 (1-2), p. 54; Deppe, M., Caroca-Canales, N., Hartmann, S., Oeschler, N., Geibel, C., (2009) J. Phys.: Condens. Matter, 21 (20), p. 206001; Hewson, A.C., (1993) The Kondo Problem to Heavy Fermions (Cambridge Studies in Magnetism), 2. , ed D Edwards and D Melville (Cambridge: Cambridge University press); Haen, P., Flouquet, J., Lapierre, F., Lejay, P., Remenyi, G., (1987) J. Low Temp. Phys., 67 (5-6), p. 391; Sakakibara, T., Tayama, T., Matamura, K., Maezawa, K., Onuki, Y., Amitsuka, H., (1995) Phys. Rev., 51 (17), p. 12030; Andreev, A.V., Vejpravov, J., Prokleška, J., Sechovsky, V., (2008) Physica, 403 (5-9), p. 744 Approved no
Call Number BT @ berisso @ Serial 599
Permanent link to this record