TY - JOUR
T1 - Successive superconducting transitions in Ta2 S2 C studied by electrical resistivity and nonlinear ac magnetic susceptibility
AU - Suzuki, Masatsugu
AU - Suzuki, Itsuko S.
AU - Noji, Takashi
AU - Koike, Yoji
AU - Walter, Jürgen
N1 - Copyright:
Copyright 2007 Elsevier B.V., All rights reserved.
PY - 2007/5/31
Y1 - 2007/5/31
N2 - Ta2 S2 C compound undergoes superconducting transitions at Tcl =3.60±0.02 K and Tcu =9.0±0.2 K. The nature of successive superconducting transitions has been studied from electrical resistivity and linear and nonlinear ac magnetic susceptibilities. The resistivity ρ at H=0 shows a local maximum near Tcu, a kinklike behavior around Tcl, and reduces to zero at below T0 =2.1 K. The ln T dependence of ρ is observed at H=50 kOe at low temperatures, which is due to a two-dimensional weak-localization effect. Below Tcu, a two-dimensional superconducting phase occurs in each TaC layer. The linear and nonlinear susceptibilities χ1″, χ3′, χ5′, and χ7′ as well as the difference δχ (= χFC - χZFC) between the field-cooled (FC) and zero-field-cooled (ZFC) susceptibilities start to appear below 6.0 K, the onset temperature of irreversibility. A drastic growth of the in-plane superconducting coherence length below 6.0 K gives rise to a three-dimensional superconducting phase below Tcl through interplanar Josephson couplings between adjacent TaC layers. The oscillatory behavior of χ3″, χ5″, and χ7″ below Tcl is related to the nonlinear behavior arising from the thermally activated flux flow.
AB - Ta2 S2 C compound undergoes superconducting transitions at Tcl =3.60±0.02 K and Tcu =9.0±0.2 K. The nature of successive superconducting transitions has been studied from electrical resistivity and linear and nonlinear ac magnetic susceptibilities. The resistivity ρ at H=0 shows a local maximum near Tcu, a kinklike behavior around Tcl, and reduces to zero at below T0 =2.1 K. The ln T dependence of ρ is observed at H=50 kOe at low temperatures, which is due to a two-dimensional weak-localization effect. Below Tcu, a two-dimensional superconducting phase occurs in each TaC layer. The linear and nonlinear susceptibilities χ1″, χ3′, χ5′, and χ7′ as well as the difference δχ (= χFC - χZFC) between the field-cooled (FC) and zero-field-cooled (ZFC) susceptibilities start to appear below 6.0 K, the onset temperature of irreversibility. A drastic growth of the in-plane superconducting coherence length below 6.0 K gives rise to a three-dimensional superconducting phase below Tcl through interplanar Josephson couplings between adjacent TaC layers. The oscillatory behavior of χ3″, χ5″, and χ7″ below Tcl is related to the nonlinear behavior arising from the thermally activated flux flow.
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U2 - 10.1103/PhysRevB.75.184536
DO - 10.1103/PhysRevB.75.184536
M3 - Article
AN - SCOPUS:34347341809
VL - 75
JO - Physical Review B - Condensed Matter and Materials Physics
JF - Physical Review B - Condensed Matter and Materials Physics
SN - 0163-1829
IS - 18
M1 - 184536
ER -