Glassy Spin Freezing and Gapless Spin Dynamics in a Spatially Anisotropic Triangular Antiferromagnet Ag2MnO2

TL;DR

This study reveals that Ag2MnO2, a spatially anisotropic triangular antiferromagnet, exhibits spin freezing into a short-range collinear state below 50 K, with gapless spin dynamics and highly two-dimensional correlations.

Contribution

It provides the first detailed neutron scattering analysis of spin freezing and gapless dynamics in Ag2MnO2, highlighting its unique two-dimensional magnetic behavior.

Findings

Spin freezing occurs below ~50 K into a short-range collinear state.

Spin fluctuations are gapless with two linear temperature-dependent relaxation rates.

Static spin correlations are highly two-dimensional.

Abstract

Using elastic and inelastic neutron scattering techniques, we show that upon cooling a spatially anisotropic triangular antiferromagnet Ag$_2$MnO$_2$ freezes below $T_f ~\sim 50$ K into short range collinear state. The static spin correlations are extremely two-dimensional, and the spin fluctuations are gapless with two characteristic relaxation rates that behave linearly with temperature.