TY - JOUR
T1 - Nodeless superconductivity in the cage-type superconductor Sc5Ru6Sn18 with preserved time-reversal symmetry
AU - Kumar, D.
AU - Kuo, C. N.
AU - Astuti, F.
AU - Shang, T.
AU - Lee, M. K.
AU - Lue, C. S.
AU - Watanabe, I.
AU - Barker, J. A.T.
AU - Shiroka, T.
AU - Chang, L. J.
N1 - Funding Information:
We acknowledge the Ministry of Science and Technology (MOST) of Taiwan, which supported the work, via the grants: MOST 104-2221-M-006-010-MY3, MOST 104-2119-M-006-017-MY3. DK would like to acknowledge MOST for the postdoctoral fellowship under project grant number MOST 105-2811-M-006-022. TS and TS acknowledge support from SNF—the Swiss National Science Foundation. Part of this work is based on experiments performed at the Swiss Muon Source µ, Paul Scherrer Institute, Villigen, Switzerland. We thank M R Lees for fruitful discussion.
Publisher Copyright:
© 2018 IOP Publishing Ltd.
PY - 2018/7/16
Y1 - 2018/7/16
N2 - We report the single-crystal synthesis and detailed investigations of the cage-type superconductor Sc5Ru6Sn18, using powder x-ray diffraction (XRD), magnetization, specific-heat and muon-spin relaxation (μSR) measurements. Sc5Ru6Sn18 crystallizes in a tetragonal structure (space group I41/acd) with lattice parameters a = 1.387(3) nm and c = 2.641(5) nm. Both DC and AC magnetization measurements prove the type-II superconductivity in Sc5Ru6Sn18 with T c ≈ 3.5(1) K, a lower critical field = 157(9) Oe and an upper critical field, = 26(1) kOe. The zero-field electronic specific-heat data are well fitted using a single-gap BCS model, with = 0.64(1) meV. The Sommerfeld constant γ varies linearly with the applied magnetic field, indicating s-wave superconductivity in Sc5Ru6Sn18. Specific-heat and transverse-field (TF) μSR measurements reveal that Sc5Ru6Sn18 is a superconductor with strong electron-phonon coupling, with TF-μSR also suggesting a single-gap s-wave character of the superconductivity. Furthermore, zero-field μSR measurements do not detect spontaneous magnetic fields below T c, hence implying that time-reversal symmetry is preserved in Sc5Ru6Sn18.
AB - We report the single-crystal synthesis and detailed investigations of the cage-type superconductor Sc5Ru6Sn18, using powder x-ray diffraction (XRD), magnetization, specific-heat and muon-spin relaxation (μSR) measurements. Sc5Ru6Sn18 crystallizes in a tetragonal structure (space group I41/acd) with lattice parameters a = 1.387(3) nm and c = 2.641(5) nm. Both DC and AC magnetization measurements prove the type-II superconductivity in Sc5Ru6Sn18 with T c ≈ 3.5(1) K, a lower critical field = 157(9) Oe and an upper critical field, = 26(1) kOe. The zero-field electronic specific-heat data are well fitted using a single-gap BCS model, with = 0.64(1) meV. The Sommerfeld constant γ varies linearly with the applied magnetic field, indicating s-wave superconductivity in Sc5Ru6Sn18. Specific-heat and transverse-field (TF) μSR measurements reveal that Sc5Ru6Sn18 is a superconductor with strong electron-phonon coupling, with TF-μSR also suggesting a single-gap s-wave character of the superconductivity. Furthermore, zero-field μSR measurements do not detect spontaneous magnetic fields below T c, hence implying that time-reversal symmetry is preserved in Sc5Ru6Sn18.
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U2 - 10.1088/1361-648X/aacf65
DO - 10.1088/1361-648X/aacf65
M3 - Article
C2 - 29947614
AN - SCOPUS:85050571302
VL - 30
JO - Journal of Physics Condensed Matter
JF - Journal of Physics Condensed Matter
SN - 0953-8984
IS - 31
M1 - 315803
ER -