Nonmagnetic Phase Transition in La$_3$TiSb$_5$ Observed in $^{121}$Sb Nuclear Quadrupole Resonance

TL;DR

This study investigates La$_3$TiSb$_5$ using resistivity and NQR measurements, revealing an incommensurate charge-density-wave transition at 110-120 K, highlighting the role of quasi-one-dimensional features and CDW instability.

Contribution

First detailed NQR and resistivity analysis of La$_3$TiSb$_5$, identifying a CDW transition in a nonmagnetic system related to antiferromagnetic compounds.

Findings

Resistivity shows a hump at 120 K indicating a phase transition.

NQR spectra split below 110 K without relaxation anomalies.

Evidence supports an incommensurate charge-density-wave transition.

Abstract

We measured the electrical resistivity and the $^{121}$Sb nuclear quadrupole resonance (NQR) spectra of La$_3$TiSb$_5$, which is a nonmagnetic reference system for a locally noncentrosymmetric antiferromagnet Ce$_3$TiSb$_5$, in order to determine its physical properties. The resistivity exhibited a hump anomaly at 120 K, suggesting a phase transition. The NQR spectra split below 110 K, whereas the nuclear spin-lattice relaxation exhibited no anomalies. These results can be explained by the incommensurate charge-density-wave (CDW) transition. This finding suggests the importance of quasi-one-dimensional characteristics and CDW instability in these systems.