Details

Autor(en) / Beteiligte

• Aslam, Mohammad
• Paul, Arpita
• Thakur, Gohil S
• Gayen, Sirshendu
• Kumar, Ritesh
• Singh, Avtar
• Das, Shekhar
• Ganguli, Ashok K
• Waghmare, Umesh V
• Sheet, Goutam

Titel

Evidence of a pseudogap driven by competing orders of multi-band origin in the ferromagnetic superconductor Sr0.5Ce0.5FBiS2

Ist Teil von

• Journal of physics. Condensed matter, 2016-05, Vol.28 (19), p.195701-195701

Ort / Verlag

England: IOP Publishing

Erscheinungsjahr

2016

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• From temperature and magnetic field dependent point-contact spectroscopy on the ferromagnetic superconductor Sr0.5Ce0.5FBiS2 (bulk superconducting Tc=2.5 K) we observe (a) a pseudogap in the normal state that sustains to a remarkably high temperature of 40 K and (b) two-fold enhancement of Tc upto 5 K in the point-contact geometry. In addition, Andreev reflection spectroscopy reveals a superconducting gap of 6 meV for certain point-contacts suggesting that the mean field Tc of this system could be approximately 40 K, the onset temperature of pseudo-gap. Our results suggest that quantum fluctuations originating from other competing orders in Sr0.5Ce0.5FBiS2 forbid a global phase coherence at high temperatures thereby suppressing Tc. Apart from the known ordering to a ferromagnetic state, our first-principles calculations reveal nesting of a multi-band Fermi surface and a significant electron-phonon coupling that could result in charge density wave-like instabilities.