Single crystal growth and superconductivity in RbNi${}_2$Se${}_2$

Abstract

We report the synthesis and characterization of RbNi${}_2$Se${}_2$, an analog of the iron chalcogenide superconductor Rb${}_x$Fe${}_2$Se${}_2$, via transport, angle resolved photoemission spectroscopy, and density functional theory calculations. A superconducting transition at $T_c$ = 1.20 K is identified. In normal state, RbNi${}_2$Se${}_2$ shows paramagnetic and Fermi liquid behaviors. A large Sommerfeld coefficient yields a heavy effective electron mass of $m^{\ast }\approx 6m_e$. In the superconducting state, zero-field electronic specific-heat data $C_{es}$ can be described by a two-gap BCS model, indicating that RbNi${}_2$Se${}_2$ is a multi-gap superconductor. Our density functional theory calculations and angle resolved photoemission spectroscopy measurements demonstrate that RbNi${}_2$Se${}_2$ exhibits relatively weak correlations and multi-band characteristics, consistent with the multi-gap superconductivity.

arXiv comment7 pages, 4 figures

References in corpus (21)

• Antiferromagnetic order and spin dynamics in iron-based superconductors
• Superconductivity and Phase Diagram in the Iron-based Arsenic-oxides ReFeAsO1-delta (Re = rare earth metal) without F-Doping
• Specific Heat of Mg ^{11}B_2
• Phenomenological two-gap model for the specific heat of MgB_2
• Superconductivity in the vicinity of antiferromagnetic order in CrAs
• Superconductivity in quasi-one-dimensional K${}_2$Cr${}_3$As${}_3$ with significant electron correlations
• Pressure induced superconductivity on the border of magnetic order in MnP
• Role of the orbital degree of freedom in iron-based superconductors
• Absence of superconductivity in bulk Nd${}_{1-x}$Sr${}_x$NiO${}_2$
• Variation of transition temperatures and residual resistivity ratio in vapor-grown FeSe
• Mixed-Valence-Driven Heavy-Fermion Behavior and Superconductivity in KNi${}_2$Se${}_2$
• Superconductivity at 5 K in quasi-one-dimensional Cr-based KCr3As3 single crystals
• Pressure-induced superconductivity and structural transition in ferromagnetic Cr2Si2Te6
• Magnetic properties in layered (K, Rb and Cs)Co2Se2 with ThCr2Si2_type structure
• Multiband Superconductivity of Heavy Electrons in TlNi2Se2 single crystal
• Stability of Superconducting Nd0.8Sr0.2NiO2 Thin Films
• Flatband-Induced Itinerant Ferromagnetism in RbCo${}_2$Se${}_2$
• Camelback-shaped band reconciles heavy electron behavior with weak electronic Coulomb correlations in superconducting TlNi2Se2
• Superconductivity in a new layered nickel-selenide CsNi2Se2
• Elucidating the magnetic and superconducting phases in the alkali metal intercalated iron chalcogenides
• The weak electronic correlations and absence of heavy Fermion state in KNi${}_2$Se${}_2$