Low-temperature magnetization in geometrically frustrated Tb2Ti2O7

TL;DR

This study investigates the low-temperature magnetic behavior of Tb2Ti2O7, revealing persistent fluctuations, glassy dynamics, and deviations from quantum spin ice predictions, highlighting complex magnetic states in frustrated pyrochlore systems.

Contribution

The paper provides new experimental data on magnetization and AC susceptibility of Tb2Ti2O7 down to 57 mK, challenging existing quantum spin ice models and revealing complex magnetic dynamics.

Findings

No clear magnetization plateau along [111] direction.

Glassy behavior and slow dynamics observed below 200 mK.

Frequency dependence of susceptibility does not match canonical spin-glass.

Abstract

The nature of the low temperature ground state of the pyrochlore compound Tb2Ti2O7 remains a puzzling issue. Dynamic fluctuations and short-range correlations persist down to 50 mK, as evidenced by microscopic probes. In parallel, magnetization measurements show irreversibilities and glassy behavior below 200 mK. We have performed magnetization and AC susceptibility measurements on four single crystals down to 57 mK. We did not observe a clear plateau in the magnetization as a function of field along the [111] direction, as suggested by the quantum spin ice model. In addition to a freezing around 200 mK, slow dynamics are observed in the AC susceptibility up to 4 K. The overall frequency dependence cannot be described by a canonical spin-glass behavior.