The Experts below are selected from a list of 22188 Experts worldwide ranked by ideXlab platform
A R Moodenbaugh - One of the best experts on this subject based on the ideXlab platform.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo2O5, containing corner-linked CoO5 square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co(2+)/Co(3+) Charge Ordering occur as well as a change in the Co2+ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Patrick M Woodward, Brett A Hunter, P Henning, P Karen, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo{sub 2} O{sub 5} , containing corner-linked CoO{sub 5} square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co{sup 2+}/Co {sup 3+} Charge Ordering occur as well as a change in the Co{sup 2+} spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering. (c) 2000 The American Physical Society.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco 2 o 5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite ${\mathrm{YBaCo}}_{2}{\mathrm{O}}_{5}$, containing corner-linked ${\mathrm{CoO}}_{5}$ square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range ${\mathrm{Co}}^{2+}/{\mathrm{Co}}^{3+}$ Charge Ordering occur as well as a change in the ${\mathrm{Co}}^{2+}$ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
S A Grigera - One of the best experts on this subject based on the ideXlab platform.
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Charge Ordering in a pure spin model dipolar spin ice
Physical Review Letters, 2013Co-Authors: R A Borzi, Demian Slobinsky, S A GrigeraAbstract:We study the dipolar spin-ice model at fixed density of single excitations, ρ, using a Monte Carlo algorithm where processes of creation and annihilation of such excitations are banned. In the limit of ρ going to zero, this model coincides with the usual dipolar spin-ice model at low temperatures, with the additional advantage that a negligible number of monopoles allows for equilibration even at the lowest temperatures. Thus, the transition to the ordered fundamental state found by Melko, den Hertog, and Gingras in 2001 is reached using simple local spin flip dynamics. As the density is increased, the monopolar nature of the excitations becomes apparent: the system shows a rich ρ vs T phase diagram with "Charge" Ordering transitions analogous to that observed for Coulomb Charges in lattices. A further layer of complexity is revealed by the existence of order both within the Charges and their associated vacuum, which can only be described in terms of spins--the true microscopic degrees of freedom of the system.
Thomas Vogt - One of the best experts on this subject based on the ideXlab platform.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo2O5, containing corner-linked CoO5 square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co(2+)/Co(3+) Charge Ordering occur as well as a change in the Co2+ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Patrick M Woodward, Brett A Hunter, P Henning, P Karen, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo{sub 2} O{sub 5} , containing corner-linked CoO{sub 5} square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co{sup 2+}/Co {sup 3+} Charge Ordering occur as well as a change in the Co{sup 2+} spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering. (c) 2000 The American Physical Society.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco 2 o 5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite ${\mathrm{YBaCo}}_{2}{\mathrm{O}}_{5}$, containing corner-linked ${\mathrm{CoO}}_{5}$ square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range ${\mathrm{Co}}^{2+}/{\mathrm{Co}}^{3+}$ Charge Ordering occur as well as a change in the ${\mathrm{Co}}^{2+}$ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
Pavel Karen - One of the best experts on this subject based on the ideXlab platform.
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eubafe2o5 weubafe2o5 w valence mixing and Charge Ordering are two separate cooperative phenomena
Journal of Solid State Chemistry, 2007Co-Authors: Pavel Karen, K. Gustafsson, Johan LindénAbstract:Mixed-valence EuBaFe2O5+wEuBaFe2O5+w exhibits a robust Verwey-type transition. The trend in the volume change suggests a first-order transition up to the nonstoichiometry level of about w=0.25w=0.25. 57Fe Mossbauer spectroscopy, differential scanning calorimetry and synchrotron X-ray powder diffraction are used to study the valence mixing and Charge Ordering in EuBaFe2O5+wEuBaFe2O5+w as a function of the nonstoichiometry parameter w. 151Eu Mossbauer spectroscopy is used as a selective probe into the ferromagnetic valence-mixing coupling along c above the Verwey transition, and reveals that increasing w destroys this coupling in favor of a G-type magnetic order in parallel with the progressive removal of the valence-mixed iron states accounted for by 57Fe Mossbauer spectroscopy. This removal proceeds according to a probability scheme of mixing between ferromagnetically coupled divalent and trivalent neighbor iron atoms along c across the R layer. In contrast, the concentration decrease of the orbital- and Charge-ordered states in EuBaFe2O5+wEuBaFe2O5+w is found to be a linear function of w. Valence mixing and Charge Ordering are therefore two separate cooperative phenomena. The enthalpy of the Verwey-type transition between these two cooperative systems is a linear function of w , which suggests that it originates from the latent heat of freezing into the long-range ordered orbital- and Charge-ordered state. The enthalpy becomes zero at the nonstoichiometry level of about w=0.25w=0.25.
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eubafe2o5 w valence mixing and Charge Ordering are two separate cooperative phenomena
Journal of Solid State Chemistry, 2007Co-Authors: Pavel Karen, K. Gustafsson, Johan LindénAbstract:Abstract Mixed-valence EuBaFe 2 O 5 + w exhibits a robust Verwey-type transition. The trend in the volume change suggests a first-order transition up to the nonstoichiometry level of about w = 0.25 . 57Fe Mossbauer spectroscopy, differential scanning calorimetry and synchrotron X-ray powder diffraction are used to study the valence mixing and Charge Ordering in EuBaFe 2 O 5 + w as a function of the nonstoichiometry parameter w. 151Eu Mossbauer spectroscopy is used as a selective probe into the ferromagnetic valence-mixing coupling along c above the Verwey transition, and reveals that increasing w destroys this coupling in favor of a G-type magnetic order in parallel with the progressive removal of the valence-mixed iron states accounted for by 57Fe Mossbauer spectroscopy. This removal proceeds according to a probability scheme of mixing between ferromagnetically coupled divalent and trivalent neighbor iron atoms along c across the R layer. In contrast, the concentration decrease of the orbital- and Charge-ordered states in EuBaFe 2 O 5 + w is found to be a linear function of w. Valence mixing and Charge Ordering are therefore two separate cooperative phenomena. The enthalpy of the Verwey-type transition between these two cooperative systems is a linear function of w, which suggests that it originates from the latent heat of freezing into the long-range ordered orbital- and Charge-ordered state. The enthalpy becomes zero at the nonstoichiometry level of about w = 0.25 .
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo2O5, containing corner-linked CoO5 square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co(2+)/Co(3+) Charge Ordering occur as well as a change in the Co2+ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco 2 o 5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite ${\mathrm{YBaCo}}_{2}{\mathrm{O}}_{5}$, containing corner-linked ${\mathrm{CoO}}_{5}$ square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range ${\mathrm{Co}}^{2+}/{\mathrm{Co}}^{3+}$ Charge Ordering occur as well as a change in the ${\mathrm{Co}}^{2+}$ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
P Henning - One of the best experts on this subject based on the ideXlab platform.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo2O5, containing corner-linked CoO5 square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co(2+)/Co(3+) Charge Ordering occur as well as a change in the Co2+ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco2o5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Patrick M Woodward, Brett A Hunter, P Henning, P Karen, A R MoodenbaughAbstract:The oxygen-deficient double perovskite YBaCo{sub 2} O{sub 5} , containing corner-linked CoO{sub 5} square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range Co{sup 2+}/Co {sup 3+} Charge Ordering occur as well as a change in the Co{sup 2+} spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering. (c) 2000 The American Physical Society.
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low to high spin state transition induced by Charge Ordering in antiferromagnetic ybaco 2 o 5
Physical Review Letters, 2000Co-Authors: Thomas Vogt, Pavel Karen, Patrick M Woodward, Brett A Hunter, P Henning, A R MoodenbaughAbstract:The oxygen-deficient double perovskite ${\mathrm{YBaCo}}_{2}{\mathrm{O}}_{5}$, containing corner-linked ${\mathrm{CoO}}_{5}$ square pyramids as principal building units, undergoes a paramagnetic to antiferromagnetic spin Ordering at 330 K. This is accompanied by a tetragonal to orthorhombic distortion. Below 220 K orbital Ordering and long-range ${\mathrm{Co}}^{2+}/{\mathrm{Co}}^{3+}$ Charge Ordering occur as well as a change in the ${\mathrm{Co}}^{2+}$ spin state from low to high spin. This transition is shown to be very sensitive to the oxygen content of the sample. To our knowledge this is the first observation of a spin-state transition induced by long-range orbital and Charge Ordering.