The low-temperature magnetic behavior of the double-layered ruthenate Sr 3Ru 2O 7, as grown from a eutectic Sr 2RuO 4-Sr 3Ru 2O 7 system, was investigated via zero- and transverse-field muon-spin rotation. The gradual increase of the muon relaxation rate observed below 2.5 K, even in the absence of applied magnetic fields, indicates the occurrence of a spontaneous breaking of time-reversal symmetry. The onset of the latter at a temperature above 1.5 K, the T c of the single phase Sr 2RuO 4, provides evidence about an unconventional superconducting state in the eutectic phase, which most likely takes place at the interface between the Sr 2RuO 4 and Sr 3Ru 2O 7 domains, or even inside the Sr 3Ru 2O 7 phase. We show that the superconducting state manifests a two-component behavior in the transverse-field response with change-over at about T=2.5 K and T=1.5 K. The comparison with zero-field μSR data in the Ru-Sr 2RuO 4 eutectic system rules out the possibility of spurious effects due to embedded Ru islands. © 2012 American Physical Society.
Shiroka, T., Fittipaldi, R., Cuoco, M., De Renzi, R., Maeno, Y., Lycett, R.J., et al. (2012). μsR studies of superconductivity in eutectically grown mixed ruthenates. PHYSICAL REVIEW. B, CONDENSED MATTER AND MATERIALS PHYSICS, 85(13), 134527-1-134527-7 [10.1103/PhysRevB.85.134527].
μsR studies of superconductivity in eutectically grown mixed ruthenates
Granata, V.;
2012-01-01
Abstract
The low-temperature magnetic behavior of the double-layered ruthenate Sr 3Ru 2O 7, as grown from a eutectic Sr 2RuO 4-Sr 3Ru 2O 7 system, was investigated via zero- and transverse-field muon-spin rotation. The gradual increase of the muon relaxation rate observed below 2.5 K, even in the absence of applied magnetic fields, indicates the occurrence of a spontaneous breaking of time-reversal symmetry. The onset of the latter at a temperature above 1.5 K, the T c of the single phase Sr 2RuO 4, provides evidence about an unconventional superconducting state in the eutectic phase, which most likely takes place at the interface between the Sr 2RuO 4 and Sr 3Ru 2O 7 domains, or even inside the Sr 3Ru 2O 7 phase. We show that the superconducting state manifests a two-component behavior in the transverse-field response with change-over at about T=2.5 K and T=1.5 K. The comparison with zero-field μSR data in the Ru-Sr 2RuO 4 eutectic system rules out the possibility of spurious effects due to embedded Ru islands. © 2012 American Physical Society.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
