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Updated: Jun 11, 2026
06:49
Radio Frequency Magnetron Sputtering of GdBa2Cu3O7−δ/ La0.67Sr0.33MnO3 Quasi-bilayer Films on SrTiO3 (STO) Single-crystal Substrates
Published on: April 12, 2019
Robust Ferromagnetically Insulating States in LaCoO3 Films through Hydrogen-Driven Multistate Topotactic Phase
Xuanchi Zhou1,2, Xiaomei Qiao1, Jiahui Ji1
1Key Laboratory of Magnetic Molecules and Magnetic Information Materials of Ministry of Education & School of Materials Science and Engineering, Shanxi Normal University, Taiyuan 030031, China.
ACS Applied Materials & Interfaces
|June 10, 2026
Summary
Hydrogenation creates room-temperature ferromagnetic insulators in LaCoO3, enabling pure spin currents for low-power spintronics. This reversible state overcomes previous material limitations.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Low-power spintronic devices require room-temperature ferromagnetic insulators to generate pure spin currents without Joule heating.
- Oxide materials face a trade-off between ferromagnetism and itinerant electrons, limiting robust ferromagnetic-insulating states.
- Hydrogenation offers a method to tune ion-electron-lattice interactions for novel magnetoelectric properties.
Purpose of the Study:
- To stabilize emergent room-temperature ferromagnetic insulators in the LaCoO3 system using hydrogenation.
- To investigate the role of hydrogen incorporation in driving phase transformations and magnetic ordering.
- To explore the potential of hydrogen-induced magnetoelectric states for low-power spintronic applications.
Main Methods:
- Topotactic phase transformations induced by hydrogen incorporation in LaCoO3.
- Oxygen vacancy ordering driven by hydrogenation.
- Analysis of spin-state crossover and double exchange interactions.
Main Results:
- Hydrogenation led to sequential phase transformations (LaCoO3-HLaCoO2.67-HLaCoO2.5) via oxygen vacancy ordering.
- Enhanced electron localization and ferromagnetic ordering were observed.
- A reversible, robust ferromagnetic-insulating state was achieved in LaCoO3 above room temperature.
Conclusions:
- Hydrogenation is a versatile approach to engineer magnetoelectric states in oxides.
- The developed LaCoO3 system exhibits potential for low-power spintronic devices due to its room-temperature ferromagnetic-insulating properties.
- This work demonstrates hydrogen-driven multistate magnetoelectric evolutions by tuning ion-electron-lattice interplay.
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