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Advanced Experimental Methods for Low-temperature Magnetotransport Measurement of Novel Materials
Published on: January 21, 2016
Enhanced Room-Temperature Geometric Magnetoresistance in Inhomogeneous Narrow-Gap Semiconductors.
1NEC Research Institute, 4 Independence Way, Princeton, NJ 08540, USA. Department of Physics and Astronomy, Ohio University, Athens, OH 45701, USA.
Science (New York, N.Y.)
|September 1, 2000
Summary
Room-temperature geometric magnetoresistance in indium antimonide disks with gold inclusions reached 750,000% at 4.0 T. This effect, driven by current deflection, shows potential for magnetic field sensing applications.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Geometric magnetoresistance (GMR) is a phenomenon observed in materials with specific geometries and magnetic fields.
- Indium antimonide (InSb) is a semiconductor with interesting electronic properties.
Purpose of the Study:
- To investigate room-temperature geometric magnetoresistance in a van der Pauw disk of indium antimonide with a gold inhomogeneity.
- To analyze the dependence of magnetoresistance on magnetic field strength and inhomogeneity size.
Main Methods:
- Fabrication of a symmetric van der Pauw disk using homogeneous nonmagnetic indium antimonide.
- Embedding a concentric gold inhomogeneity within the disk.
- Measurement of resistance at various magnetic fields (0.05 T, 0.25 T, 4.0 T) at room temperature.
Main Results:
- Achieved exceptionally high room-temperature geometric magnetoresistance: 100% at 0.05 T, 9100% at 0.25 T, and 750,000% at 4.0 T.
- Observed field-independent resistance up to an onset field for large inhomogeneities, followed by rapid increase.
- Correlated the observed magnetoresistance with the field-dependent deflection of current around the gold inhomogeneity.
Conclusions:
- The study demonstrates a significant room-temperature geometric magnetoresistance effect in InSb/Au systems.
- The results highlight the potential of such structures for sensitive magnetic field detection.
- Current deflection around inhomogeneities is the key mechanism governing the observed high magnetoresistance.
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