Two dimensional frustrated magnetic state in superconducting RuSr2Eu1.5Ce0.5Cu2O10 (Ru-1222)
arXiv:0812.0137 · doi:10.1103/PhysRevB.79.054506
Abstract
In this paper we investigate the magnetic state and the role of the crystalline structure in RuSr2Eu1.5Ce0.5Cu2O10 (Ru-1222). Measurements were made in the isomorphic series (Nb1-xRux)Sr2Eu1.5Ce0.5Cu2O10 [(Nb,Ru)-1222], with x between 0 and 1. 3D XY fluctuations above the magnetic transition were not observed in Ru-1222, suggesting a weak inter-plane coupling between the RuO2 layers. The compositional dependence of the magnetic susceptibility shows a rapid broadening with increasing Nb content, explained in terms of a cluster-glass state. The variation of several superconducting parameters as a function of Ru content is linear in the whole concentration range, with no jumps at the critical concentration for which percolation of long range order is expected. 3D Arrhenius and Vogel-Fulcher-type dependencies fail to describe the dynamic properties. Fitting of a generalized Vogel-Fulcher-type dependence, with ln(tau/tau0) = A(T-T0)^-B, yield B = 2.0, in excellent agreement with Monte Carlo simulations for 2D systems. The value deduced for T0 agrees well with the re-opening of hysteresis in the M(H) curves. The observed superconducting and magnetic features are explained in terms of a scenario of 2D magnetic islands at the RuO2 layers, with no long range magnetic order.
submitted to Phys. Rev. B
References in corpus (14)
- Coexistence of ferromagnetism and superconductivity in the hybrid ruthenate-cuprate compound RuSr_2GdCu_2O_8 studied by muon spin rotation (μSR) and DC-magnetization
- Antiferromagnetic Order of the Ru and Gd in Superconducting RuSr2GdCu2O8
- Superconductivity in Ferromagnetic RuSr2GdCu2O8
- Spin Glass Behavior in RuSr2Gd1.5Ce0.5Cu2O10
- Magnetic-Superconducting phase-diagram of Eu2-xCexRuSr2Cu2O10
- Ruthenocuprates RuSr2(Eu,Ce)2Cu2O10: Intrinsic magnetic multilayers
- Evidence for Possible Phase-Separations in RuSr2(Gd,Ce)2Cu2O10-delta
- The possible origin of the higher magnetic phase transition in RuSr2Eu1.5Ce0.5Cu2O10 (Ru-1222)
- Magnetic Transitions and Ferromagnetic Clusters in RuSr2(Eu,Ce)2Cu2O10+d
- Magneto-transport study of intra- and intergrain transitions in the magnetic superconductors RuSr2GdCu2O8 and RuSr2(Gd1.5Ce0.5)Cu2O10
- Magnetic and superconducting properties of RuSr2 Gd1.5Ce0.5Cu2O10-x samples: dependence on the oxygen content and ageing effects
- Search for Magnetic Order in Superconducting RuSr2Eu1.2Ce0.8Cu2O10
- Oxygen non-stoichiometry in Ru-1212 and Ru-1222 magnetosuperconductors
- Separation Between Antiferromagnetic and Ferromagnetic Transitions in Ru_1-xCu_xSr_2EuCu_2O_8+d