Spin-ice dynamics of pyrochlore Dy2GaSbO7 with enhanced Pauling zero-point entropy

TL;DR

This study investigates the spin-ice behavior and low-temperature properties of Dy2GaSbO7, revealing enhanced zero-point entropy and disordered spin freezing due to chemical disorder, differing from canonical spin-ice materials.

Contribution

It provides new insights into spin-ice dynamics in a mixed pyrochlore with enhanced entropy caused by chemical disorder and pressure effects.

Findings

Spins freeze at 3.1 K into a disordered state

Enhanced zero-point entropy observed compared to canonical spin-ice

Disorder and chemical pressure influence spin dynamics

Abstract

We report the low-temperature magnetothermal properties and spin dynamics of a mixed pyrochlore, Dy2GaSbO7 through the coordination of measurements of dc magnetization, ac susceptibility, and heat capacity, and CF computation. In Dy2GaSbO7, the spins freeze at temperature Tice = 3.1 K, corresponding to dynamical spin-freezing into a disordered state in compliance with the spin-ice rules, but with enhanced zero-point entropy, unlike cannonical dipolar spin-ice materials, Dy2Ti2O7 and Ho2Ti2O7, due to random disorder and varied chemical pressure of B-site (GaSb tetrahedra) ions.