Magnetic and transport properties of i-$R$-Cd icosahedral quasicrystals ($R$ = Y, Gd-Tm)

TL;DR

This study characterizes the magnetic and transport properties of recently discovered i-$R$-Cd quasicrystals, revealing diverse magnetic behaviors including spin-glass states and weak diamagnetism, with detailed thermodynamic and structural insights.

Contribution

It provides the first comprehensive analysis of the magnetic, transport, and structural properties of i-$R$-Cd quasicrystals across a range of rare-earth elements, highlighting their complex magnetic phenomena.

Findings

i-Gd-Cd exhibits spin-glass behavior below 4.6 K.

Resistivity is approximately 300 μΩ·cm and weakly temperature-dependent.

Freezing temperatures deviate from de Gennes scaling, indicating crystal electric field effects.

Abstract

We present a detailed characterization of the recently discovered i-$R$-Cd ($R$ = Y, Gd-Tm) binary quasicrystals by means of x-ray diffraction, temperature-dependent dc and ac magnetization, temperature-dependent resistance and temperature-dependent specific heat measurements. Structurally, the broadening of x-ray diffraction peaks found for i-$R$-Cd is dominated by frozen-in phason strain, which is essentially independent of $R$. i-Y-Cd is weakly diamagnetic and manifests a temperature-independent susceptibility. i-Gd-Cd can be characterized as a spin-glass below 4.6 K via dc magnetization cusp, a third order non-linear magnetic susceptibility peak, a frequency-dependent freezing temperature and a broad maximum in the specific heat. i-$R$-Cd ($R$ = Ho-Tm) is similar to i-Gd-Cd in terms of features observed in thermodynamic measurements. i-Tb-Cd and i-Dy-Cd do not show a clear cusp in their zero-field-cooled dc magnetization data, but instead show a more rounded, broad local maximum. The resistivity for i-$R$-Cd is of order 300 $\mu \Omega$ cm and weakly temperature-dependent. The characteristic freezing temperatures for i-$R$-Cd ($R$ = Gd-Tm) deviate from the de Gennes scaling, in a manner consistent with crystal electric field splitting induced local moment anisotropy.