# Dynamic scaling analysis of the long-range RKKY Ising spin glass Dy$_{x}$Y$_{1-x}$Ru$_{2}$Si$_{2}$

## TL;DR

This study investigates the critical behavior of a long-range RKKY Ising spin glass, revealing unique universality class characteristics and evidence for replica-symmetry-breaking through dynamic scaling analysis of susceptibilities.

## Contribution

It provides the first detailed critical exponents and scaling analysis for a long-range RKKY Ising spin glass, showing distinct universality class features and RSB evidence.

## Key findings

- Critical exponents differ from canonical SGs.
- Finite-temperature SG transition persists under magnetic field.
- Phase transition line follows a specific field dependence.

## Abstract

Dynamic scaling analyses of linear and nonlinear ac susceptibilities in a model magnet of the long-rang RKKY Ising spin glass (SG) Dy$_{x}$Y$_{1-x}$Ru$_{2}$Si$_{2}$ were examined. The obtained set of the critical exponents, $\gamma$ $\sim$ 1, $\beta$ $\sim$ 1, $\delta$ $\sim$ 2, and $z\nu$ $\sim$ 3.4, indicates the SG phase transition belongs to a different universality class from either the canonical (Heisenberg) or the short-range Ising SGs. The analyses also reveal a finite-temperature SG transition with the same critical exponents under a magnetic field and the phase transition line $T_{\mbox{g}}(H)$ described by $T_{\mbox{g}}(H)$ $=$ $T_{\mbox{g}}(0)(1-AH^{2/\phi})$ with $\phi$ $\sim$ 2. The crossover exponent $\phi$ obeys the scaling relation $\phi$ $=$ $\gamma + \beta$ within the margin of errors. These results strongly suggest the spontaneous replica-symmetry-breaking (RSB) with a {\it non- or marginal-mean-field universality class} in the long-range RKKY Ising SG.