Thermal evolution of magnetic-excitation spectrum of PrB6

Abstract

The magnetic dynamic response of a PrB₆ single crystal has been studied using inelastic neutron scattering in a temperature range of 10–120 K, which is above the temperatures of the phase transitions to the magnetic-ordered state. The study is aimed at revealing peculiarities of the state with a low magnetic moment in a temperature range of 7 K < T ≤ 20 K, which was identified in a number of magnetometric experiments. In addition to a quasielastic signal, a weak-dispersion excitation with an energy of ~1 meV has been detected, which exists at temperatures below 24 K. The results have been analyzed from the viewpoint of the formation of a spatially nonuniform state based on domains with short-range magnetic correlations at temperatures of 10–20 K. Judging by the dispersion of excitations, the character of the correlation is similar to that observed in a state with long-range magnetic order which arises at lower temperatures.