Solution growth of Ce-Pd-In single crystals: characterization of the heavy-fermion superconductor Ce2PdIn8

TL;DR

This study reports the growth, characterization, and superconducting properties of Ce2PdIn8 single crystals, revealing their magnetic behavior and sample-dependent superconductivity, advancing understanding of heavy-fermion superconductors.

Contribution

It introduces a method for growing high-quality Ce2PdIn8 single crystals and provides detailed magnetic and superconducting characterization, highlighting sample-dependent superconductivity.

Findings

Ce2PdIn8 crystals exhibit paramagnetic behavior with anisotropic susceptibility.

Superconductivity observed below 0.69 K with sample-dependent transition features.

Magnetic susceptibility follows Curie-Weiss law above 70 K with different Curie temperatures.

Abstract

Solution growth of single crystals of the recently reported new compound Ce2PdIn8 was investigated. When growing from a stoichiometry in a range 2:1:20 - 2:1:35, single crystals of CeIn3 covered by a thin (~50 um) single-crystalline layer of Ce2PdIn8 were mostly obtained. Using palladium richer compositions the thickness of the Ce2PdIn8 layers were increased, which allowed mechanical extraction of single-phase slabs of the desired compound suitable for a thorough study of magnetism and superconductivity. In some solution growth products also CePd3In6 (LaNi3In6 - type of structure) and traces of phases with the stoichiometry CePd2In7, Ce1.5Pd1.5In7 (determined only by EDX) have been identified. Magnetic measurements of the Ce2PdIn8 single crystals reveal paramagnetic behaviour of the Ce3+ ions with significant magnetocrystalline anisotropy. Above 70 K the magnetic susceptibility follows the Curie-Weiss law with considerably different values of the paramagnetic Curie temperature, for the magnetic field applied along the a- (-90 K) and c-(-50 K) axis. Below the reported critical temperature for superconductivity Tc (0.69 K) the electrical resistivity drops to zero. Comparative measurements of the electrical resistivity, heat capacity and AC susceptibility of several crystals reveal that the superconducting transition is strongly sample-dependent.