2014/11/06 by Yusei Shimizu, Shunichiro Kittaka, Toshiro Sakakibara +5
Materials Science · Mathematics · Physics and Astronomy · #Advanced Condensed Matter Physics #Condensed matter physics #Electron #Energy (signal processing) #Field (mathematics) #Geometry #Iron-based superconductors research #Mathematics #Nuclear physics #Orientation (vector space) #Particle physics #Physics #Quantum mechanics #Quasiparticle #Rare-earth and actinide compounds #Superconductivity #cond-mat.str-el #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevlett.114.147002
published as Phys. Rev. Lett. 114, 147002 (2015) · 5 pages, 4 figures
arxiv created 2014/11/06 · openalex publication_date 2015/04/07 · arxiv updated 2015/04/13 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
Low-energy quasiparticle excitations in the superconducting (SC) state of UBe13 were studied by means of specific-heat (C) measurements in a rotating field. Quite unexpectedly, the magnetic-field dependence of C(H) is linear in H with no angular dependence at low fields in the SC state, implying that the gap is fully open over the Fermi surfaces, in stark contrast to previous expectations. In addition, a characteristic cubic anisotropy of C(H) was observed above 2 T with a maximum (minimum) for H∥[001] ([111]) within the (11[over ¯]0) plane, in the normal as well as in the SC states. This oscillation possibly originates from the anisotropic response of the heavy quasiparticle bands, and might be a key to understand the unusual properties of UBe13.