From Cooperative Paramagnet to Néel Order in Y_2Ru_2O_7

Abstract

Spin correlations in the pyrochlore antiferromagnet Y_2Ru_2O_7 with Curie-Weiss temperature ${\Theta }_{CW}=-1100$ K and critical temperature T_N=77 K were examined through neutron scattering. For $T_N<T<{\Theta }_{CW}/3$ the data show spin relaxation with a rate $\hslash \Gamma =1.17(9)k_{B}T$. For T<T_N spectral weight moves to higher energies with substantial changes up to $4\times k_B{T}_N$. For T<<T_N there is a $\Delta =11(1)$ meV energy gap and a pronounced spectral maximum at 19.7 meV. Throughout the temperature range examined the wave vector dependence of inelastic scattering exhibits a broad peak for $Qd\approx 3.8$ (d is Ru-Ru spacing) consistent with dipolar spin correlations.

4 pages, 4 figures, submitted to PRB-RC

References in corpus (2)

• Flux expulsion and greedy bosons: frustrated magnets at large N
• Effective Hamiltonians for large-S pyrochlore antiferromagnet

Cited by in corpus (7)

• Magnetic Pyrochlore Oxides
• Spin Dynamics in Pyrochlore Heisenberg Antiferromagnets
• Quadrupolar Singlet Ground State of Praseodymium in a Modulated Pyrochlore
• Frustration, strain and phase co-existence in the mixed valent hexagonal iridate Ba${}_3$NaIr${}_2$O${}_9$
• Goldstone modes in the emergent gauge fields of a frustrated magnet
• Metal-insulator transitions in pyrochlore oxides
• Geometrically frustrated antiferromagnets: statistical mechanics and dynamics