Low temperature magneto-dielectric coupling in nanoscale layered SmFe0.5Co0.5O3 perovskite

Abstract

In this study, we determined the different physical characteristics of nanoscale layered mixed Fe-Co layers of orthoferrite SmFe 0.5 Co 0.5 O 3 based on magnetic and dielectric measurements.Magnetization analyzes showed that the system was antiferromagnetic with a magnetic transition around 310 K and two spin-reorientation transitions at around 192 K and 22 K. In this phase, the antisymmetric exchange interaction induced weak ferromagnetism due to canting of the magnetic spins in a similar manner to the Ln-Fe-Co system. Importantly, this nanoscale layered perovskite also exhibited a positive magneto-dielectric effect of around 2.5% (100 K) and the value decreased on both sides of this temperature. We analyzed the conditions related to the existence of magnetic and dielectric coupling in terms of the magnetic interactions between the cations as well as the spin-lattice interactions in the low temperature range.

Structural and magnetic characterization of spin canted mixed ferrite-cobaltites: LnFe0.5Co0.5O3 (Ln = Eu and Dy)

“…For understanding the exact behaviour of magnetic interactions below room temperature, the field dependent isothermal magnetization needs to be investigated at different temperatures. perovskite, which is clearly in accordance with the previously reported results [11][12][13]15,16].…”

“…Moreover, the AFM ordering of Fe-Co sublattice conforms with the AFM behaviour of Fe 3+ -O-Co 3+ , Fe 3+ -O-Fe 3+ and Co 3+ -O-Co 3+ interactions [12,13,15]. The magnetic transition near 300 K for both perovskites may be due to canting of the antiferromagnetically aligned magnetic spins (which is well known for orthoferrites).…”

“…It is worth mentioning that with decreasing the lanthanide cation T N value decreases, which also supported by the data from our group [13,15]. Nevertheless, the transition temperature T N is almost 50 K lower for LnFe 0.5 Co 0.5 O 3 series and also the temperature variation with size is significantly weaker compared to La and Sm-phases [13,15]. Therefore, we considered it important to investigate the missing member i.e.…”

“…Both the perovskites exhibit a weak ferromagnetic behavior below the room temperature, arising from a canting of the AFM spins. The DM interaction could be the basis of weak ferromagnetism in these mixed ferrite-cobaltites, which has been well established for perovskite orthoferrites [1][2][3][11][12][13].…”

“…Also, entropy plays a dominant role in determining the pure phase and stable structure of reaction products. Previous investigations on the doped orthoferrites have motivated us to synthesize doped perovskite with smaller size of lanthanides in similar conditions [13,15]. Therefore, we have utilized sol-gel route synthesis to avoid higher temperature as it has explicit inherent advantages over the solid-state reaction synthesis methods.…”