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Updated: May 31, 2026
11:54
Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
An ultrasonic study on complex charge ordering phenomena for La(1-x)Sr(x)FeO(3)
1Laboratory of Advanced Functional Materials and Devices, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
Summary
Complex charge ordering in La(1-x)Sr(x)FeO(3) was investigated using ultrasonic velocity and resistivity. Different doping levels reveal distinct charge ordering states and transitions, including Fe(3+)/Fe(4+) ordering and Fe-O octahedron distortions.
Area of Science:
- Materials Science
- Condensed Matter Physics
- Solid State Chemistry
Background:
- Polycrystalline La(1-x)Sr(x)FeO(3) exhibits complex charge ordering phenomena.
- Understanding these phenomena is crucial for developing advanced electronic materials.
Purpose of the Study:
- To investigate the complex charge ordering phenomena in La(1-x)Sr(x)FeO(3) for 1/3≤x≤2/3.
- To characterize the relationship between doping concentration and charge ordering behavior.
Main Methods:
- Low-temperature magnetization measurements.
- Electrical resistivity measurements.
- Longitudinal ultrasonic velocity (V(l)) measurements.
Main Results:
- At low doping (1/3≤x≤0.5), a dramatic V(l) increase below 210 K suggests short-range Fe(3+)/Fe(4+) charge ordering.
- At high doping (0.5
- La(1/3)Sr(2/3)FeO(3) shows a V(l) softening below 181 K due to Fe-O octahedron breathing distortion.
- Sound velocity anomalies differ between doping levels, confirming complex charge ordering.
Conclusions:
- The study reveals distinct charge ordering phenomena in La(1-x)Sr(x)FeO(3) dependent on Sr doping concentration.
- Ultrasonic velocity and resistivity measurements provide sensitive probes for characterizing these complex electronic states.
- The findings contribute to a deeper understanding of charge ordering in perovskite oxides.
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