Magnetic Pyrochlore Oxides

  title={Magnetic Pyrochlore Oxides},
  author={J. Gardner and M. Gingras and J. Greedan},
  journal={Reviews of Modern Physics},
Within the past 20 years or so, there has occurred an explosion of interest in the magnetic behavior of pyrochlore oxides of the type $A_{2}^{3+}$$B_{2}^{4+}$O$_{7}$ where $A$ is a rare-earth ion and $B$ is usually a transition metal. Both the $A$ and $B$ sites form a network of corner-sharing tetrahedra which is the quintessential framework for a geometrically frustrated magnet. In these systems the natural tendency to form long range ordered ground states in accord with the Third Law is… Expand
Magnetic Pyrochlore Oxides
Within the past 20 years or so, there has occurred an explosion of interest in the magnetic behavior of pyrochlore oxides of the type $A_{2}^{3+}$$B_{2}^{4+}$O$_{7}$ where $A$ is a rare-earth ion andExpand
Crossover between tricritical and Lifshitz points in pyrochlore FeF3
Pyrochlore FeF$_{3}$ (pyr-FeF$_{3}$) is a Heisenberg anti-ferromagnetic (AF) with a magnetic susceptibility deviating from the Curie-Weiss law, even at the room temperature. This compound shows aExpand
Frustration under pressure: Exotic magnetism in new pyrochlore oxides
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We report the magnetic characterization of the frustrated transition metal pyrochlore NaCaCo$_2$F$_7$. This material has high spin Co$^{2+}$ in CoF$_6$ octahedra in a pyrochlore lattice, andExpand
Effects of stuffing on the atomic and electronic structure of the pyrochlore Yb 2 Ti 2 O 7
There are reasons to believe that the ground state of the magnetic rare earth pyrochlore Yb$_2$Ti$_2$O$_7$ is on the boundary between competing ground states. We have carried out $\mathrm{\textit{abExpand
Degenerate ground state in the classical pyrochlore antiferromagnet Na3Mn(CO3)2Cl
In an ideal classical pyrochlore antiferromagnet without perturbations, an infinite degeneracy at a ground state leads to absence of a magnetic order and spin-glass transition. Here we presentExpand
Dilute stuffing in the pyrochlore iridate Eu 2 Ir 2 O 7
The pyrochlore Eu$_2$Ir$_2$O$_7$ has recently attracted significant attention as a candidate Weyl semimetal. The previous reports on this compound unanimously show a thermally induced metal toExpand
Effect of chemical pressure on the crystal electric field states of erbium pyrochlore magnets
We have carried out a systematic study of the crystal electric field excitations in the family of cubic pyrochlores Er$_2B_2$O$_7$, with $B=$~Ti, Ge, Pt, and Sn, using neutron spectroscopy. AllExpand
Absence of long-range order in an XY pyrochlore antiferromagnet Er2AlSbO7
Rare-earth pyrochlores are known to exhibit exotic magnetic phenomena. We report a study of crystal growth and characterizations of a new rare-earth compound ${\mathrm{Er}}_{2}{\mathrm{AlSbO}}_{7}$,Expand
Local-Ising-type magnetic order and metamagnetism in the rare-earth pyrogermanate Er 2 Ge 2 O 7
The recent discoveries of proximate quantum spin-liquid compounds and their potential application in quantum computing informs the search for new candidate materials for quantum spin-ice andExpand


Magnetic Pyrochlore Oxides
Within the past 20 years or so, there has occurred an explosion of interest in the magnetic behavior of pyrochlore oxides of the type $A_{2}^{3+}$$B_{2}^{4+}$O$_{7}$ where $A$ is a rare-earth ion andExpand
We report a detailed study of the pyrochlore Ho{sub 2}Ti{sub 2}O{sub 7}, in which the magnetic ions (Ho{sup 3+}) are ferromagnetically coupled with J{approximately}1 K . We show that the presence ofExpand
Mean-field approach to magnetic ordering in highly frustrated pyrochlores.
A general form of the mean-field theory is developed for dealing with {ital n}-component classical vector spins on any lattice and Calculations for the pyrochlore problem show that the Fourier modes of the system are completely degenerate for all wave vectors in the first Brillouin zone. Expand
Magnetic Ordering in Gold-Iron Alloys
In an attempt to characterize the magnetic ordering in $\mathrm{Au}\mathrm{Fe}$ alloys, systematic studies were made of the temperature dependences of the thermoelectric power $S$ and the low-fieldExpand
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In the pyrochlore lattice, the magnetic ions sit at the corners of a framework of corner-sharing tetrahedra. It is well known that this lattice results in a very high degree of geometricalExpand
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Abstract Rare earth-based materials have played a central role in recent efforts to understand the very unconventional behavior of geometrically frustrated magnetic materials. In particular, rareExpand
Origin of Spin Ice Behavior in Ising Pyrochlore Magnets with Long Range Dipole Interactions: an Insight from Mean-Field Theory
Recent experiments suggest that the Ising pyrochlore magnets ${\rm Ho_{2}Ti_{2}O_{7}}$ and ${\rm Dy_{2}Ti_{2}O_{7}}$ display qualitative properties of the ferromagnetic nearest neighbor spin iceExpand
Superconductivity in a pyrochlore oxide, Cd2Re2O7
We make the first report that a metallic pyrochlore oxide, Cd2Re2O7, exhibits type II superconductivity at 1.1 K. The pyrochlore oxide is known to be a geometrically frustrated system, which includesExpand
Spin Dynamics of the Magnetoresistive Pyrochlore Tl 2 Mn 2 O 7
Neutron scattering has been used to study the magnetic order and spin dynamics of the colossal magnetoresistive pyrochlore Tl_2Mn_2O_7. On cooling from the paramagnetic state, magnetic correlationsExpand
Thermodynamic and single-ion properties of Tb3+ within the collective paramagnetic-spin liquid state of the frustrated pyrochlore antiferromagnet Tb2Ti2O7
In a recent letter [Phys. Rev. Lett. {\bf 82}, 1012 (1999)] it was found that the Tb$^{3+}$ magnetic moments in the Tb$_2$Ti$_2$O$_7$ pyrochlore lattice of corner-sharing tetrahedra remain in a {\itExpand