Impact of disorder in Nd-based pyrochlore magnets

Mélanie Léger, Florianne Vayer, Monica Ciomaga Hatnean, Françoise Damay, Claudia Decorse, David Berardan, Björn Fåk, Jean-Marc Zanotti, Quentin Berrod, Jacques Ollivier, Jan P. Embs, Tom Fennell, Denis Sheptyakov, Sylvain Petit, and Elsa Lhotel

We study the stability of the antiferromagnetic all-in–all-out state observed in dipolar-octupolar pyrochlores that have neodymium as the magnetic species. Different types of disorder are considered, either affecting the immediate environment of the Nd3+ ion or substituting it with a nonmagnetic ion. Starting from the well-studied Nd2⁢Zr2⁢O7 compound, Ti substitution on the Zr site and dilution on the Nd magnetic site with La substitution are investigated. The recently discovered entropy stabilized compound NdMox, which exhibits a high degree of disorder on the nonmagnetic site is also studied. Using a range of experimental techniques, especially very low-temperature magnetization and neutron scattering, we show that the all-in–all-out state is very robust and withstands substitutional disorder up to large rates. From these measurements, we estimate the Hamiltonian parameters and discuss their evolution in the framework of the phase diagram of dipolar-octupolar pyrochlore magnets.

https://doi.org/10.1103/PhysRevB.109.224416