Researchers from Lithuania's Center for Physical Sciences and Technology and Kaunas University of Technology have reported a novel hybrid magnetic sensor that combines the unique properties of manganite and graphene to measure both the magnitude and direction of a magnetic field.
The schematic drawing of the hybrid sensor. Image from: Scientific Reports
The sensor consists of a nanostructured manganite film to detect the magnetic field strength and a graphene layer to determine the angle between the magnetic field and the sensor plane. This dual sensor approach increases sensitivity over a wide range of magnetic field strengths and provides directional information, making it ideal for applications such as object positioning and navigation.
The sensor design, based on a voltage divider configuration, has been optimized to achieve high sensitivity.
Experimental results in pulsed magnetic fields up to 21 T demonstrated the increased sensitivity offered by the graphene-manganite combination.
In addition, a measurement system for recording and processing data was developed that enables real-time measurement of the magnetic field magnitude and its orientation.
In conclusion, the team's novel hybrid manganite-graphene sensor is capable of measuring both the magnitude and direction of magnetic fields with increased sensitivity. The combination of the negative magnetoresistance of manganite and the positive magnetoresistance of graphene improved the sensor’s performance and enabled accurate detection over a wide range of magnetic field strengths and angles. The optimized design, including careful adjustment of electrode spacing and layer dimensions, resulted in a significant increase in magnetoresistance and sensitivity, especially when the magnetic field was perpendicular to the sensor’s surface. The integrated data acquisition system allowed the sensor outputs to be processed in real time, enabling both the magnetic field and its orientation to be accurately determined.
The hybrid sensor developed in this work demonstrates the potential for applications requiring reliable magnetic field magnitude and direction measurements over a wide magnetic field and operating temperature ranges.
