Negative Colossal Magnetoresistance Driven by Carrier Type in the Ferromagnetic Mott Insulator GaV 4 S 8
| Autor: | Etienne Janod, Laurent Cario, Viorel Pop, Sabrina Salmon, Frédéric Christien, Benoit Corraze, Vincent Guiot, E. Dorolti |
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| Přispěvatelé: | Institut des Matériaux Jean Rouxel (IMN), Université de Nantes - UFR des Sciences et des Techniques (UN UFR ST), Université de Nantes (UN)-Université de Nantes (UN)-Centre National de la Recherche Scientifique (CNRS)-Institut de Chimie du CNRS (INC)-Ecole Polytechnique de l'Université de Nantes (EPUN), Université de Nantes (UN)-Université de Nantes (UN), Babes-Bolyai University [Cluj-Napoca] (UBB) |
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Materials science
Colossal magnetoresistance Magnetoresistance Condensed matter physics General Chemical Engineering Mott insulator Doping General Chemistry Electron 3. Good health Condensed Matter::Materials Science Ferromagnetism Electrical resistivity and conductivity Condensed Matter::Superconductivity Materials Chemistry [PHYS.COND.CM-MS]Physics [physics]/Condensed Matter [cond-mat]/Materials Science [cond-mat.mtrl-sci] Curie temperature Condensed Matter::Strongly Correlated Electrons ComputingMilieux_MISCELLANEOUS |
| Zdroj: | Chemistry of Materials Chemistry of Materials, American Chemical Society, 2015, 27 (12), pp.4398-4404. ⟨10.1021/acs.chemmater.5b01168⟩ |
| ISSN: | 0897-4756 1520-5002 |
| DOI: | 10.1021/acs.chemmater.5b01168⟩ |
| Popis: | We report here a study on the evolution of structural and electronic properties of the lacunar spinel compounds GaV4S8 with charge doping. In this ferromagnetic (FM) Mott insulator, the heterovalent substitutions of Ga3+ by Zn2+ or Ge4+ allow induction of charge doping either by holes or by electrons. We show that electron-doped GaV4S8 displays a bulk, negative, and colossal magnetoresistance (CMR) with a relative drop of resistivity reaching −80% at 7 T in the vicinity of the Curie temperature. Conversely, hole-doped GaV4S8 does not display any negative CMR but a classical positive magnetoresistance. This asymmetric electron–hole doping effect challenges the common view stating that CMR effects in doped FM Mott insulators depends only on the density of carrier and not on their electron/hole nature. We show that a simple model based on multiorbital effects and Hund’s rule is able to capture the presence (absence) of negative CMR in electron- (hole-) doped GaV4S8. |
| Databáze: | OpenAIRE |
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