Time Evolution of the Structural, Electronic, and Magnetic Phases in Relaxed SrCoO₃ Thin Films

Abstract

The topotactic phase transition in the transition-metal oxides via redox reactions has wide-ranging applications in solid oxide fuel cells, neuromorphic computations, mottronics, and memory devices. Probing the intermediate states in the path of such phase transition is key to realizing the topotactic phase evolution. Here, we have tracked such a phase transition path by allowing the relaxed SrCoO3 film to naturally reduce toward the SrCoO2.5 phase and investigated the time-dependent correlated structural, electronic, and magnetic states in the intermediate SrCoO x systems. The strained film, on the other hand, is very much stable in terms of structural, electronic, and magnetic properties. The magnetic phase coexistence and the correlation between the magnetic exchange interaction and the O 2p hole density are also realized in the SrCoO x systems. Our study greatly improves the fundamental understanding of the topotactic phase evolution by uncovering the hidden correlated phases in SrCoO x systems, which encourages us to investigate the same in another topotactic phase transition material, SrFeO x , for the pursuits in developing such phase transition-related technological potential applications.

High-temperature insulating ferromagnetic state in charge-disproportionated and spin-state-disproportionated strained SrCoO2.5 thin film

“…Thus, it can be stated 17 The stronger O 2p-Co 3d hybridization is also consistent with the observed higher degree of CoO 6 O h and CoO 4 T d ordering in the 30 nm film relative to the 150 nm film since the structural disorder deteriorates the hybridization strength. 49 Tuning the magnetic ground state by altering the electronic correlation parameters shows a way to modulate the magnetic state via applying an electric field 50 besides strain engineering, which provides a new route toward energy-efficient spintronics in SCO-based systems. 51 In this line, modification of physical properties by ferroelectric/piezoelectric strain through substrate's lattice parameter modification via electric field enables an engineering method that allows for the creation of tailored states similar to manganite thin films on Pb(Mg 1/3 Nb 2/3 )O 3 -PbTiO 3 substrates.…”

Heteroaromatic Diazirines Are Essential Building Blocks for Material and Medicinal Chemistry

“…Recently, use of (3-trifluoromethyl)phenyldiazirine (TPD) has been widely increasing in materials science for creation of crosslinking of component parts of organic light-emitting diodes [ 15 , 16 ], for primers for fiber-reinforced polymer composites [ 17 ], and for patterning of wearable elastic circuits [ 18 ]. Despite the success of TPD as a photocross-coupling agent, in order to establish functional materials more efficiently and easily with versatile photocrosslinking, there is a need to improve the photolabeling performance of TPD.…”

Surface Stability Analysis with H Adsorption Affected the Magnetic Fluctuation of Brownmillerite SrCoO2.5 Based on the Electron Counting Model by Layers

“…Strontium cobalt oxide (SrCoO 3‑δ ) thin films have drawn a lot of research attention because of the unique tunability of electronic, magnetic, and optical properties. − Recent experimental results demonstrate that ionic liquid gating plays a significant role in tuning the magnetic order of brownmillerite SrCoO 2.5 (BM-SCO) and HSrCoO 2.5 (HSCO) thin films with excellent stability and reversibility. , Specifically, incorporation of excess H ions was observed in the HSCO and changed the magnetic order from antiferromagnetic (AFM) to weakly ferromagnetic (WFM). However, the WFM with an insulating nature cannot be explained by any known magnetic mechanism in bulk. − Current theoretical calculations suggest that in the fully hydrogenic case (i.e., H/SCO = 1:1), the system shows an AFM ground state. Ferromagnetic (FM) can only be achieved if holes are introduced into the system.…”