Ground-state instability of the Mott insulator Ca2RuO4:: Impact of slight La doping on the metal-insulator transition and magnetic ordering

被引:45
作者
Cao, G [1 ]
McCall, S
Dobrosavljevic, V
Alexander, CS
Crow, JE
Guertin, RP
机构
[1] Natl High Magnet Field Lab, Tallahassee, FL 32310 USA
[2] Tufts Univ, Dept Phys, Medford, MA 02155 USA
来源
PHYSICAL REVIEW B | 2000年 / 61卷 / 08期
关键词
D O I
10.1103/PhysRevB.61.R5053
中图分类号
T [工业技术];
学科分类号
08 ;
摘要
Ca2RuO4 is a Mott system with a structurally driven metal-insulator transition at T-MI = 357 K and Neel temperature at T-N = 110 K. Slight substitution of trivalent La for bivalent Ca in Ca2RuO4 drastically reduces T-MI and the electrical resistivity, simultaneously precipitating robust ferromagnetism in the antiferromagnetic host. T-C is conspicuously and consistently lower than T-MI, suggesting that the metal-insulator transition is not driven by the magnetic instability. The La substitution:also results in a rapid increase in both the Pauli susceptibility and electronic specific heat coefficient, and:a crossover from hopping conductivity to disordered metallic behavior at low temperatures. These dramatic changes;underline the subtlety of the competition between the antiferromagnetic and ferromagnetic coupling:and a near degeneracy of the ground state in Ca2RuO4.
引用
收藏
页码:R5053 / R5057
页数:5
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  • [1] Destruction of the Mott insulating ground state of Ca2RuO4 by a structural transition
    Alexander, CS
    Cao, G
    Dobrosavljevic, V
    McCall, S
    Crow, JE
    Lochner, E
    Guertin, RP
    [J]. PHYSICAL REVIEW B, 1999, 60 (12) : R8422 - R8425
  • [2] Structural stability of Sr2RuO4
    Braden, M
    Reichardt, W
    Nishizaki, S
    Mori, Y
    Maeno, Y
    [J]. PHYSICAL REVIEW B, 1998, 57 (02): : 1236 - 1240
  • [3] Crystal and magnetic structure of Ca2RuO4:: Magnetoelastic coupling and the metal-insulator transition
    Braden, M
    Andre, G
    Nakatsuji, S
    Maeno, Y
    [J]. PHYSICAL REVIEW B, 1998, 58 (02) : 847 - 861
  • [4] Multiple magnetic phase transitions in single-crystal (Sr1-xCax)(3)Ru2O7 for 0<=X<=1.0
    Cao, G
    McCall, SC
    Crow, JE
    Guertin, RP
    [J]. PHYSICAL REVIEW B, 1997, 56 (09): : 5387 - 5394
  • [5] Observation of itinerant ferromagnetism in layered Sr3Ru2O7 single crystals
    Cao, G
    McCall, S
    Crow, JE
    [J]. PHYSICAL REVIEW B, 1997, 55 (02): : R672 - R675
  • [6] Observation of a metallic antiferromagnetic phase and metal to nonmetal transition in Ca3Ru2O7
    Cao, G
    McCall, S
    Crow, JE
    Guertin, RP
    [J]. PHYSICAL REVIEW LETTERS, 1997, 78 (09) : 1751 - 1754
  • [7] From antiferromagnetic insulator to ferromagnetic metal: a brief review of the layered ruthenates
    Cao, G
    Alexander, CS
    McCall, S
    Crow, JE
    Guertin, RP
    [J]. MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY, 1999, 63 (1-2): : 76 - 82
  • [8] Localization and transport in pseudoternary ruthenates
    Cao, G
    Dobrosavljevic, V
    McCall, S
    Crow, JE
    Guertin, RP
    [J]. PHYSICA B-CONDENSED MATTER, 1999, 259-61 : 951 - 953
  • [9] Ferromagnetism in Sr4Ru3O10: Relationship to other layered metallic oxides
    Cao, G
    McCall, SK
    Crow, JE
    Guertin, RP
    [J]. PHYSICAL REVIEW B, 1997, 56 (10) : R5740 - R5743
  • [10] Magnetic and transport properties of single-crystal Ca2RuO4: Relationship to superconducting Sr2RuO4
    Cao, G
    McCall, S
    Shepard, M
    Crow, JE
    Guertin, RP
    [J]. PHYSICAL REVIEW B, 1997, 56 (06) : R2916 - R2919