Quasi-quantized Hall response in bulk InAs

Area of Science:

• Condensed Matter Physics
• Materials Science

Background:

• The quasi-quantized Hall effect (QQHE) is the three-dimensional (3D) analog of the integer quantum Hall effect (QHE).
• QQHE has been observed in layered materials with 3D anisotropic Fermi surfaces.
• Theoretical predictions suggest QQHE may occur in a broader range of bulk materials.

Purpose of the Study:

• To investigate the occurrence of 3D QQHE in bulk semiconductor InAs.
• To compare experimental observations with theoretical predictions for 3D QQHE in materials with parabolic electron bands.

Main Methods:

• Experimental measurement of Hall conductivity and longitudinal resistivity in n-type InAs.
• Analysis of the onset of plateau-like features in Hall conductivity.
• Comparison of experimental results with theoretical calculations.

Main Results:

• Quasi-quantized plateau-like features were observed in the Hall conductivity of InAs.
• The onset of these features scaled with a specific formula related to the conductance quantum.
• A Shubnikov-de Haas minimum in longitudinal resistivity accompanied the Hall conductivity features.

Conclusions:

• Experimental results in InAs are consistent with predictions for 3D QQHE.
• The 3D QQHE appears to be a generic effect observable in materials with small Fermi surfaces under strong magnetic fields.