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Author (up) Jaime, M.; Movshovich, R.; Stewart, G.R.; Beyermann, W.P.; Berisso, M.G.; Hundley, M.F.; Canfield, P.C.; Sarrao, J.L. openurl 
  Title Closing the spin gap in the Kondo insulator Ce3Bi4Pt3 at high magnetic fields Type Journal Article
  Year 2000 Publication Nature Abbreviated Journal  
  Volume 405 Issue 6783 Pages 160-163  
  Keywords  
  Abstract Kondo insulator materials(1)-such as CeRhAs, CeRhSb, YbB12, Ce3Bi4Pt3 and SmB6-are 3d, 4f and 5f intermetallic compounds that have attracted considerable interest in recent years(2-5). At high temperatures, they behave like metals. But as temperature is reduced, an energy gap opens in the conduction band at the Fermi energy and the materials become insulating. This contrasts with other f-electron compounds, which are metallic at all temperatures. The formation of the gap in Kondo insulators has been proposed to be a consequence of hybridization between the conduction band and the f-electron levels(6,7), giving a 'spin' gap. If this is indeed the case, metallic behaviour should be recovered when the gap is closed by changing external parameters, such as magnetic field or pressure. Some experimental evidence suggests that the gap can be closed in SmB6 (refs 5, 8) and YbB12 (ref. 9). Here we present specific-heat measurements of Ce3Bi4Pt3 in d.c. and pulsed magnetic fields up to 60 tesla. Numerical results and the analysis of our data using the Coqblin-Schrieffer model demonstrate unambiguously a field-induced insulator-to-metal transition.  
  Address  
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  Language Summary Language Original Title  
  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN 0028-0836 ISBN Medium  
  Area Expedition Conference  
  Notes ISI:000087080100043 Approved no  
  Call Number BT @ hernan @ Serial 300  
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Author (up) Lora-Serrano, R.; Correa, V. F.; Adriano,C.; Giles, C.; Duque, J.G.S.; Granado, E.; Pagliuso, P.G.; Murphy, T.P.; Palm, E.C.; Tozer, S.W.; Lacerda, A.H.; Sarrao, J.L. doi  openurl
  Title First order magnetic transition and magnetoelastic effects in Sm2IrIn8 Type Journal Article
  Year 2008 Publication Physica B Abbreviated Journal  
  Volume 403 Issue 5-9 Pages 1365-1367  
  Keywords First order magnetic phase transition; Magnetotrictive effects; CEF effects  
  Abstract We report measurements of temperature dependent heat capacity, thermal expansion and high resolution X-ray diffraction (XRD) taken on single crystals of Sm2IrIn8 intermetallic compound. This compound belongs to the RmMnIn3m+2n family (R=rare earth, m=1, 2, n=0, 1 and M=Rh, Ir and Co) which includes a number of heavy fermion superconductors for R=Ce. Particularly, Sm2IrIn8 is the only member of this family to present a first order magnetic phase transition (FOMT). Both thermal expansion and heat capacity data show very pronounced sharps peaks at View the MathML source consistent with an FOMT. The linear thermal-expansion coefficient is anisotropic and both c-axis and basal ab plane coefficients change discontinuously at 14.2 K. This change is negative for both direction in contrast to what was found for other members of family such as Ce2RhIn8 and CeRhIn5. The zero-field high resolution XRD data at 14.2 K shows no evidence for a tetragonal-to-orthorhombic structural phase transition. We discuss our results considering tetragonal crystalline field effects (CEF), quadupolar interactions, antiferromagnetic domains and magnetoelastic effects.  
  Address  
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  Series Editor Series Title Abbreviated Series Title  
  Series Volume Series Issue Edition  
  ISSN ISBN Medium  
  Area Expedition Conference International Conference on Strongly Correlated Electron Systems  
  Notes Approved no  
  Call Number BT @ hernan @ Serial 307  
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