Avoided quantum criticality and cluster-glass formation in itinerant ferromagnet Sr${}_{1-x}$(La${}_{0.5}$K${}_{0.5}$)${}_x$RuO${}_3$

Abstract

We demonstrate that the cluster-glass state emerges as ferromagnetic quantum criticality is avoided in itinerant ferromagnet Sr1-x(La0.5K0.5)xRuO3. In this compound, the ferromagnetic order is suppressed by increasing x, and then disappears at the critical concentration: x=0.5. In this x range, the present study reveals that no prominent feature is ascribed to the quantum critical fluctuations in specific heat. Instead, ac magnetic susceptibility exhibits a broad peak due to spontaneous spin freezing, and the peak temperature depends significantly on the frequency of the applied ac magnetic field. Furthermore, specific heat is enhanced within a wide temperature range, whereas specific heat shows no salient anomaly associated with spin freezing. These features are characteristics of the formation of cluster-glass; in particular, the observed frequency variations in ac magnetic susceptibility are well described by the Vogel-Fulcher law. We compare the features concerning the suppression of the ferromagnetic order in this doped compound with those in isostructural Ca- and La-doped SrRuO3, and suggest that a local correlated disorder effect and the very small coherence of itinerant Ru 4d electrons are responsible for the cluster-glass formation instead of the quantum phase transition in Sr1-x(La0.5K0.5)xRuO3.

arXiv comment9 pages, 7 figures, to appear in Phys. Rev. Materials

References in corpus (22)

• Saturation of electrical resistivity
• Transport Properties, Thermodynamic Properties, and Electronic Structure of SrRuO3
• Electronic structure and magnetism in Ru based perovskites
• Non-Fermi liquid behavior of SrRuO_3 -- evidence from infrared conductivity
• Phase separation and suppression of critical dynamics at quantum transitions of itinerant magnets: MnSi and (Sr${}_{1-x}$Ca${}_x$)RuO${}_3$
• Quantum Griffiths effects and smeared phase transitions in metals: theory and experiment
• Spin Glass Behavior in RuSr2Gd1.5Ce0.5Cu2O10
• Quasiparticle Mass Enhancement and Temperature Dependence of the Electronic Structure of Ferromagnetic SrRuO3 Thin Films
• From itinerant ferromagnetism to insulating antiferromagnetism: A magnetic and transport study of single crystal SrRu1-xMnxO3
• Spectral evolution in (Ca,Sr)RuO_3 near the Mott-Hubbard transition
• On the Origin of the Non-Fermi Liquid Behavior of SrRuO_{3}
• Structural and physical properties of $SrM{n}_{1-x}R{u}_x{O}_3$ perovskites
• Lattice effects on ferromagnetism in perovskite ruthenates
• Disorder promotes ferromagnetism: Rounding of the quantum phase transition in Sr_{1-x}Ca_xRuO_3
• Violation of the Mott-Ioffe-Regel Limit: High-temperature Resistivity of Itinerant Magnets Srn+1RunO3n+1 (n=2,3,infinity) and CaRuO3
• Antiferromagnetic Order in Disorder-Induced Insulating Phase of SrRu_{1-x}Mn_xO_3 (0.4<x<0.6)
• Investigation of the ferromagnetic transition in the correlated 4d perovskites SrRu${}_{1-x}$Rh${}_x$O${}_3$
• Long-range and local crystal structures of the Sr1-xCaxRuO3 Perovskites
• Ferromagnetic cluster-glass state in itinerant electron system Sr1-xLaxRuO3
• Ferromagnetic Cluster Glass Phase Embedded in a Paramagnetic and Metallic Host in Non-uniform Magnetic System CaRu_{1-x}Sc_{x}O_{3}
• Muon Spin Relaxation and Neutron Diffraction Studies of Cluster-Glass States in Sr1-xLaxRuO3
• Correlation effect in Sr${}_{1-x}$La${}_x$RuO${}_3$ studied by soft x-ray photoemission spectroscopy