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arXiv · 2111.05920

Influence of the Magnetic Sub-Lattices in the Double Perovskite Compound LaCaNiReO$_6$

Abstract

The magnetism of double perovskites is a complex phenomenon, determined from intra- or interatomic magnetic moment interactions, and strongly influenced by geometry. We take advantage of the complementary length and time scales of the muon spin rotation, relaxation and resonance ($\mu^+$SR) microscopic technique and bulk AC/DC magnetic susceptibility measurements to study the magnetic phases of the LaCaNiReO$_6$ double perovskite. As a result we are able to discern and report a newly found dynamic phase transition and the formation of magnetic domains below and above the known magnetic transition of this compound at T$_N$ = 103 K. $\mu^+$SR, serving as a local probe at crystallographic interstitial sites, reveals a transition from a metastable ferrimagnetic ordering below T = 103 K to a stable one below T = 30 K. The fast and slow collective dynamic state of this system are investigated. Between 103 K < T < 230 K, the following two magnetic environments appear, a dense spin region and a static-dilute spin region. The paramagnetic state is obtained only above T > 270 K. An evolution of the interaction between Ni and Re magnetic sublattices in this geometrically frustrated fcc perovskite structure, is revealed as a function of temperature and magnetic field, through the critical behaviour and thermal evolution of microscopic and macroscopic physical quantities.

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Konstantinos Papadopoulos, Ola Kenji Forslund, Elisabetta Nocerino, Fredrik O. L. Johansson, Gediminas Simutis, Nami Matsubara, Gerald Morris, Bassam Hitti, Donald Arseneau, Jean-Christophe Orain, Vladimir Pomjakushin, Peter Svedlindh, Daniel Andreica, Lars Börjesson, Jun Sugiyama, Martin Månsson, Yasmine Sassa. 2021-11-10. Influence of the Magnetic Sub-Lattices in the Double Perovskite Compound LaCaNiReO$_6$. https://doi.org/10.1103/physrevb.106.214410

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