On the superconductivity of the Li$_{x}$RhB$_{y}$ compositions

TL;DR

This study reports the discovery of superconductivity in Li$_{x}$RhB$_{y}$ intermetallics with a critical temperature around 2-3 K, examining their structural, electronic, and magnetic properties across various compositions.

Contribution

It provides the first detailed analysis of the superconducting and magnetic properties of Li$_{x}$RhB$_{y}$ compounds over a wide compositional range, including structural and thermodynamic insights.

Findings

Superconductivity observed at $T_c$ ≈ 2-3 K in Li$_{x}$RhB$_{y}$.

Unit-cell structure is cubic with space group $Pnar{3}n$.

Quadratic temperature dependence of electronic specific heat and paramagnetic Meissner Effect observed.

Abstract

We observed superconductivity ($T_{c}$ $\simeq$2-3 K) in Li$_{x}$RhB$_{y}$ intermetallics wherein $x$ and $y$ vary over a wide compositional range. The crystal structure consists of cubic unit-cell ($a$ $\simeq$ 12.1 \AA ) with centro-symmetric space group $Pn\bar{3}n$. A weak but positive pressure-induced increase of $T_{c}$ was observed. The correlations between the composition and each of the followings were followed over a wide range of $x$ and $y$: the unit-cell dimensions, $T_{c}$ , Sommerfeld coefficient $\gamma$, Debye temperature $\theta_{D}$, and critical fields $H$$_{c1}$ and $H$$_{c2}$. The thermal evolution of the electronic specific heat within the superconducting phase was observed to follow a quadratic-in-$T$ behavior. In addition, a paramagnetic Meissner Effect (PME) is manifested during a low-field-cooled magnetization cycle. This manifestation of quadratic-in-$T$ behavior and PME feature will be discussed.