TY - JOUR
T1 - Incommensurate spin-density wave and magnetic lock-in transition in CaFe4As3
AU - Manuel, P.
AU - Chapon, L. C.
AU - Todorov, I. S.
AU - Chung, D. Y.
AU - Castellan, J. P.
AU - Rosenkranz, S.
AU - Osborn, R.
AU - Toledano, P.
AU - Kanatzidis, M. G.
N1 - Copyright:
Copyright 2010 Elsevier B.V., All rights reserved.
PY - 2010/5/3
Y1 - 2010/5/3
N2 - The magnetic structure for the recently synthesized iron-arsenide compound CaFe4As3 has been studied by neutron-powder diffraction. Long-range magnetic order is detected below 85 K, with an incommensurate modulation described by the propagation vector k= (0,δ,0), δ∼0.39. Below ∼25 K, our measurements detect a first-order phase transition where δ locks into the commensurate value 3/8. A model of the magnetic structure is proposed for both temperature regimes, based on Rietveld refinements of the powder data and symmetry considerations. The structures correspond to longitudinal spin-density waves with magnetic moments directed along the b axis. A Landau analysis captures the change in thermodynamic quantities observed at the two magnetic transitions, in particular, the drop in resistivity at the lock-in transition.
AB - The magnetic structure for the recently synthesized iron-arsenide compound CaFe4As3 has been studied by neutron-powder diffraction. Long-range magnetic order is detected below 85 K, with an incommensurate modulation described by the propagation vector k= (0,δ,0), δ∼0.39. Below ∼25 K, our measurements detect a first-order phase transition where δ locks into the commensurate value 3/8. A model of the magnetic structure is proposed for both temperature regimes, based on Rietveld refinements of the powder data and symmetry considerations. The structures correspond to longitudinal spin-density waves with magnetic moments directed along the b axis. A Landau analysis captures the change in thermodynamic quantities observed at the two magnetic transitions, in particular, the drop in resistivity at the lock-in transition.
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U2 - 10.1103/PhysRevB.81.184402
DO - 10.1103/PhysRevB.81.184402
M3 - Article
AN - SCOPUS:77955442051
VL - 81
JO - Physical Review B-Condensed Matter
JF - Physical Review B-Condensed Matter
SN - 1098-0121
IS - 18
M1 - 184402
ER -