Crystal field excitations in the new pyrochlore compounds Nd2-xYbxTi2O7

This study investigates a novel approach to dilution or mixing of cations in pyrochlores, where the magnetic lattice site accommodates two rare-earth cations simultaneously. Specifically, the compounds Nd2-xYbxTi2O7 (x = 1.5, 1.0, 0.5) are explored, leveraging the distinct properties of Nd3+ and Yb3+ ions, including their Kramers-type nature and differing ionic radii sizes. This unique arrangement is anticipated to induce fundamental modifications in the crystalline electric field (CEF) levels. The primary objective is to elucidate the CEF levels of Nd2-xYbxTi2O7, potentially revealing a new energetic configuration resulting from the presence of two different cations with doublet ground states. Through this investigation, a precise understanding of the implications of Nd/Yb mixing on the magnetism of the pyrochlore Nd2-xYbxTi2O7 is sought, offering insights into complex phenomena or emergent magnetic ground states than can be expected in this series.