Peculiarities of the 4I9/2-(4G5/2+2G7/2) transition behavior in Nd0.5Gd0.5Fe3(BO3)4 and local magnetic properties of the crystal in the excited states

TL;DR

This study investigates the peculiar behavior of specific electronic transitions in Nd0.5Gd0.5Fe3(BO3)4, revealing state-dependent magnetic properties and deviations in selection rules, with implications for understanding magnetic ordering.

Contribution

It provides new insights into the transition behavior and local magnetic properties of Nd0.5Gd0.5Fe3(BO3)4 in various excited states, highlighting state-dependent magnetic phenomena.

Findings

Local magnetic properties depend on the excited state.

Weak ferromagnetic moments appear in some excited states.

Selection rules vary between paramagnetic and magnetically ordered states.

Abstract

Polarized absorption spectra of single-crystal Nd0.5Gd0.5Fe3(BO3)4 were studied in the region of transition 4I9/2-(4G5/2+2G7/2) in Nd3+ ion as a function of temperature (2-34 K) and magnetic field (0-65 kOe). Spectra of natural circular dichroism were measured in the range of 5-40 K. It was found out that the local magnetic properties in vicinity of the excited ion substantially depend on its state. In particular, a weak ferromagnetic moment appears in some excited states. It was found out that selection rules for electron transitions in magnetically ordered state substantially deviate from those in paramagnetic state of the crystal. They are different for different transitions and they are very sensitive to orientation of the sublattice magnetic moment relative to the light polarization. In the spectrum of the natural circular dichroism, the transition is revealed which is not observed in the absorption spectrum.