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Ferromagnetic cluster-glass phase in Ca(Co1-xIrx)2-yAs2 crystals

Journal Article · · Physical Review B
In this study, single crystals of Ca(Co1-xIrx)2-yAs2 with 0≤x≤0.35 and 0.10≤y≤0.14 have been grown using the self-flux technique and characterized by single-crystal x-ray diffraction (XRD), energy-dispersive x-ray spectroscopy, magnetization M, and magnetic susceptibility χ measurements versus temperature T, magnetic field H, and time t, and heat-capacity Cp(H,T) measurements. The XRD refinements reveal that all the Ir-substituted crystals crystallize in a collapsed-tetragonal structure as does the parent CaCo2-yAs2 compound. A small 3.3% Ir substitution for Co in CaCo1.86As2 drastically lowers the A-type antiferromagnetic (AFM) transition temperature TN from 52 to 23 K with a significant enhancement of the Sommerfeld electronic heat-capacity coefficient. The A-type AFM structure consists of ab-plane layers of spins ferromagnetically aligned along the c axis with AFM alignment of the spins in adjacent layers along this axis. The positive Weiss temperatures obtained from Curie-Weiss fits to the χ(T>TN) data indicate that the dominant magnetic interactions are ferromagnetic (FM) for all x. A magnetic phase boundary is inferred to be present between x=0.14 and x=0.17 from a discontinuity in the x dependencies of the effective moment and Weiss temperature in the Curie-Weiss fits. FM fluctuations that strongly increase with increasing x are also revealed from the χ(T) data. Furthermore, the magnetic ground state for x≥0.17 is a spin glass as indicated by hysteresis in χ(T) between field-cooled and zero-field-cooled measurements and from the relaxation of M in a small field that exhibits a stretched-exponential time dependence. The spin glass has a small FM component to the ordering and is hence inferred to be comprised of small FM clusters. The competing AFM and FM interactions along with crystallographic disorder associated with Ir substitution are inferred to be responsible for the development of a FM cluster-glass phase. A logarithmic T dependence of Cp at low T for x=0.14 is consistent with the presence of significant FM quantum fluctuations. This composition is near the T=0 boundary at x≈0.16 between the A-type AFM phase containing ferromagnetically-aligned layers of spins and the FM cluster-glass phase.
Research Organization:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division
Grant/Contract Number:
AC02-07CH11358
OSTI ID:
1639043
Report Number(s):
IS-J--10,265
Journal Information:
Physical Review B, Journal Name: Physical Review B Journal Issue: 2 Vol. 102; ISSN 2469-9950
Publisher:
American Physical Society (APS)Copyright Statement
Country of Publication:
United States
Language:
English

References (66)

Superconductivity and Crystal Structures of (Ba 1− x K x )Fe 2 As 2 ( x =0-1) journal September 2008
Itinerant ferromagnetism induced by electron doping in SrCo2As2 journal May 2019
Magnetic phase inhomogeneity in frustrated intermetallic compound Sm2Ni0.87Si2.87 journal April 2018
Bulk superconductivity at 2.6 K in undoped RbFe2As2 journal December 2010
High-temperature superconductivity in iron-based materials journal August 2010
Magnetism and its microscopic origin in iron-based high-temperature superconductors journal October 2012
Ferromagnetic behavior induced by La-doping in SrCo 2 As 2 journal January 2018
Quantum critical fluctuations in layered YFe 2 Al 10 journal September 2014
The puzzle of high temperature superconductivity in layered iron pnictides and chalcogenides journal October 2010
Relation between the specific heat and susceptibility of an antiferromagnet journal October 1962
Pressure-induced unconventional superconductivity near a quantum critical point in CaFe 2 As 2 journal April 2010
Superconductivity and spin–orbit coupling in non-centrosymmetric materials: a review journal January 2017
Effects of Impurities on Spin Fluctuations in Almost Ferromagnetic Metals journal June 1968
Antiferromagnetic stacking of ferromagnetic layers and doping-controlled phase competition in Ca 1 − x Sr x Co 2 − y As 2 journal July 2019
Competing magnetic phases and itinerant magnetic frustration in SrCo 2 As 2 journal August 2019
Flat-band magnetism and helical magnetic order in Ni-doped SrCo 2 As 2 journal September 2019
Non-Fermi-liquid types of behavior associated with a magnetic quantum critical point in Sr ( Co 1 − x Ni x ) 2 As 2 single crystals journal September 2019
Helical magnetic ordering in Sr ( Co 1 − x Ni x ) 2 As 2 journal October 2019
Time decay of the remanent magnetization in a Cu Mn spin glass journal January 1986
Effect of a nonzero temperature on quantum critical points in itinerant fermion systems journal September 1993
Coexistence of ferromagnetic and glassy behavior in the La 0.5 Sr 0.5 CoO 3 perovskite compound journal February 1999
Magnetic relaxation phenomena and cluster glass properties of La 0.7 − x Y x Ca 0.3 MnO 3 manganites journal September 2001
Ferromagnetic cluster glass behavior in U 2 IrSi 3 journal November 2003
Stretched exponential relaxation arising from a continuous sum of exponential decays journal November 2006
Pressure-induced volume-collapsed tetragonal phase of CaFe 2 As 2 as seen via neutron scattering journal November 2008
Renormalized behavior and proximity of BaCo 2 As 2 to a magnetic quantum critical point journal January 2009
Lattice collapse and quenching of magnetism in CaFe 2 As 2 under pressure: A single-crystal neutron and x-ray diffraction investigation journal January 2009
Evolution of the bulk properties, structure, magnetic order, and superconductivity with Ni doping in CaFe 2 − x Ni x As 2 journal October 2009
Unconventional pairing in the iron arsenide superconductors journal April 2010
Ferromagnetic cluster spin-glass behavior in PrRhSn 3 journal January 2012
Field-induced spin-flop transitions in single-crystalline CaCo 2 As 2 journal April 2012
Metamagnetic transition in Ca 1 − x Sr x Co 2 As 2 ( x = 0 and 0.1) single crystals journal June 2012
Crystal growth and physical properties of SrCu 2 As 2 , SrCu 2 Sb 2 , and BaCu 2 Sb 2 journal June 2012
Crystallographic, electronic, thermal, and magnetic properties of single-crystal SrCo 2 As 2 journal July 2013
Crystal and magnetic structure of CaCo 1.86 As 2 studied by x-ray and neutron diffraction journal November 2013
Physical properties of metallic antiferromagnetic CaCo 1.86 As 2 single crystals journal June 2014
α − RuCl 3 : A spin-orbit assisted Mott insulator on a honeycomb lattice journal July 2014
Crystallography and physical properties of BaCo 2 As 2 , Ba 0.94 K 0.06 Co 2 As 2 , and Ba 0.78 K 0.22 Co 2 As 2 journal August 2014
Coexistence of antiferromagnetic and ferromagnetic spin correlations in SrCo 2 As 2 revealed by Co 59 and As 75 NMR journal June 2015
Role of spin-orbit coupling and evolution of the electronic structure of WTe 2 under an external magnetic field journal September 2015
Suppression of magnetic order in CaCo 1.86 As 2 with Fe substitution: Magnetization, neutron diffraction, and x-ray diffraction studies of Ca ( Co 1 − x Fe x ) y As 2 journal February 2017
Superconductivity at 38 K in the Iron Arsenide ( Ba 1 − x K x ) Fe 2 As 2 journal September 2008
Superconducting Fe-Based Compounds ( A 1 − x Sr x ) Fe 2 As 2 with A = K and Cs with Transition Temperatures up to 37 K journal September 2008
Superconducting State in SrFe 2 − x Co x As 2 by Internal Doping of the Iron Arsenide Layers journal November 2008
Superconductivity Induced by Phosphorus Doping and Its Coexistence with Ferromagnetism in EuFe 2 ( As 0.7 P 0.3 ) 2 journal April 2009
Orbital Magnetism and Spin-Orbit Effects in the Electronic Structure of BaIrO 3 journal November 2010
Stripe Antiferromagnetic Spin Fluctuations in SrCo 2 As 2 journal October 2013
Competing Magnetic Fluctuations in Iron Pnictide Superconductors: Role of Ferromagnetic Spin Correlations Revealed by NMR journal September 2015
Effective One-Dimensional Coupling in the Highly Frustrated Square-Lattice Itinerant Magnet CaCo 2 − y As 2 journal October 2017
Anomalous Composition-Induced Crossover in the Magnetic Properties of the Itinerant-Electron Antiferromagnet Ca 1 − x Sr x Co 2 − y As 2 journal December 2017
Coexistence of Ferromagnetic and Stripe Antiferromagnetic Spin Fluctuations in SrCo 2 As 2 journal March 2019
Dynamic measurements in a Heisenberg spin glass: CuMn journal May 1994
Non-Fermi-Liquid Behavior at a Ferromagnetic Quantum Critical Point in Ni x Pd 1 − x journal May 1999
Prominent Role of Spin-Orbit Coupling in FeSe Revealed by Inelastic Neutron Scattering journal May 2017
Spin glasses: Experimental facts, theoretical concepts, and open questions journal October 1986
Superconductivity in iron compounds journal December 2011
A common thread: The pairing interaction for unconventional superconductors journal October 2012
Colloquium : The unexpected properties of alkali metal iron selenide superconductors journal May 2013
Antiferromagnetic order and spin dynamics in iron-based superconductors journal August 2015
VESTA 3 for three-dimensional visualization of crystal, volumetric and morphology data journal October 2011
Comparison of silver and molybdenum microfocus X-ray sources for single-crystal structure determination journal January 2015
Crystal structure refinement with SHELXL journal January 2015
SHELXT – Integrated space-group and crystal-structure determination journal January 2015
FeAs-Based Superconductivity: A Case Study of the Effects of Transition Metal Doping on BaFe 2 As 2 journal August 2010
The magnetic phase diagram of Ca 1−x Sr x Co 2 As 2 single crystals journal December 2013
The role of spin-orbit coupling for the superconducting state in Sr 2 RuO 4 journal February 2000