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Room-Temperature Ferromagnetic Ultrathin α-MoO3:Te Nanoflakes
Dong Jin Lee1, Youngmin Lee1, Young H Kwon1
1Quantum-functional Semiconductor Research Center , Dongguk University - Seoul 04623 , Korea.
ACS Nano
|July 12, 2019
Summary
Room-temperature ferromagnetism was achieved in ultrathin tellurium-doped molybdenum trioxide (α-MoO3:Te) nanoflakes. This discovery, driven by magnetic polarons and oxygen vacancies, opens doors for spin-based electronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Wide bandgap semiconductor α-MoO3 has potential for spin functionalities.
- Achieving stable ferromagnetism in such materials at room temperature is a significant challenge.
Purpose of the Study:
- To materialize room-temperature ferromagnetism in ultrathin α-MoO3 doped with tellurium (α-MoO3:Te).
- To investigate the underlying mechanism responsible for the observed ferromagnetism.
Main Methods:
- Growth of 2D-like ultrathin α-MoO3:Te nanoflakes via vapor-phase epitaxy.
- Characterization using Raman spectroscopy to confirm structural integrity and doping effects.
- Analysis of magnetic properties to identify ferromagnetism.
Main Results:
- Successful synthesis of ultrathin α-MoO3:Te nanoflakes exhibiting room-temperature ferromagnetism.
- Observation of Ag Raman band indicating the presence of the α-MoO3 lattice.
- Formation of pentacoordinated Mo5+ sites due to Te doping, leading to bound magnetic polarons coupled with oxygen vacancies.
Conclusions:
- Room-temperature ferromagnetism is materialized in α-MoO3:Te nanoflakes through the formation of magnetic polarons.
- The findings suggest a pathway towards realizing spin functionalities in wide bandgap semiconductor α-MoO3:Te.
- This work contributes to the development of novel magnetic materials for spintronic applications.
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