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Negative Magnetoresistance in the GeSn Strip
Kaixiang Shu1, Nan Wang2,3, Nengjie Huo1
1Institute of Semiconductors, South China Normal University, Guangzhou 510631, P.R. China.
ACS Applied Materials & Interfaces
|June 15, 2021
Summary
Researchers observed large negative magnetoresistance in GeSn alloys, consistent with the chiral anomaly in topological semimetals. This finding opens new avenues for exploring exotic phenomena in Dirac semimetals.
Area of Science:
- Condensed matter physics
- Materials science
- Solid-state physics
Background:
- Topological materials exhibiting exotic phenomena, like the chiral anomaly in Dirac or Weyl semimetals, are gaining significant research interest.
- While TaAs and Na3Bi are known topological semimetals, theoretical studies suggest group IV GeSn alloys could also be Dirac semimetals, compatible with silicon technology.
Purpose of the Study:
- To investigate the potential of GeSn alloys as topological Dirac semimetals.
- To explore the observation of negative magnetoresistance (MR) in GeSn alloys and its relation to exotic phenomena.
Main Methods:
- Fabrication of a GeSn alloy strip.
- Experimental measurement of magnetoresistance under varying magnetic and electric field orientations.
Main Results:
- Observation of a large negative magnetoresistance (MR) in the GeSn strip.
- The negative MR was found to be sensitive to the relative orientation of the magnetic and electric fields.
- This specific MR behavior was observed only when the magnetic field was parallel to the electric field.
Conclusions:
- The observed orientation-dependent negative MR in GeSn is consistent with the chiral anomaly characteristic of topological semimetals.
- This study validates GeSn alloys as a promising new class of Dirac semimetals.
- The findings pave the way for further research into negative MR and its underlying mechanisms in these materials.
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