Open AccessSuperconductivity in a new layered triangular-lattice system Li2IrSi2
Author(s) -
Kazumasa Horigane,
Kazumasa A. Takeuchi,
Daiki Hyakumura,
Rie Horie,
Toyoto Sato,
Toshiya Muranaka,
Kenji Kawashima,
Hirofumi Ishii,
Yoshihiro Kubozono,
Shin Ichi Orimo,
Masaaki Isobe,
Jun Akimitsu
Publication year - 2019
Publication title -
new journal of physics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.584
H-Index - 190
ISSN - 1367-2630
DOI - 10.1088/1367-2630/ab4159
Subject(s) - physics , superconductivity , condensed matter physics , critical field , coherence length , electrical resistivity and conductivity , lattice (music) , crystal structure , hexagonal lattice , magnetic field , crystallography , antiferromagnetism , quantum mechanics , chemistry , acoustics
We report on the crystal structure and superconducting properties of a novel iridium-silicide, namely Li 2 IrSi 2 . It has a Ag 2 NiO 2 -type structure (space group R-3m) with the lattice parameters a = 4.028 30(6) Å and c = 13.161 80(15) Å. The crystal structure comprises IrSi 2 and double Li layers stacked alternately along the c -axis. The IrSi 2 layer includes a two-dimensional Ir equilateral-triangular lattice. Electrical resistivity and static magnetic measurements revealed that Li 2 IrSi 2 is a type-II superconductor with critical temperature ( T c ) of 3.3 K. We estimated the following superconducting parameters: lower critical field H c1 (0) ∼ 42 Oe, upper critical field H c2 (0) ∼ 1.7 kOe, penetration depth λ 0 ∼ 265 nm, coherence length ξ 0 ∼ 44 nm, and Ginzburg–Landau parameter κ GL ∼ 6.02. The specific-heat data suggested that superconductivity in Li 2 IrSi 2 could be attributed to weak-coupling Cooper pairs.