Carrier Engineering in Polarization-Sensitive Black Phosphorus van der Waals Junctions

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Van der Waals heterostructures with p-type black phosphorus (BP) show promise for electronic and optoelectronic devices.
• Carrier transport anisotropy and its relation to linear dichroism in BP heterostructures remain underexplored.

Purpose of the Study:

• To demonstrate a novel van der Waals device utilizing an orientation-perpendicular black phosphorus (BP) homojunction.
• To investigate the gate-tunable rectification and polarization-sensitive properties arising from anisotropic band structures.

Main Methods:

• Fabrication of a van der Waals device with BP homojunctions featuring perpendicular crystal orientations (armchair and zigzag).
• Characterization of device performance, including gate-tunable diode-like rectification.
• Investigation of polarization-sensitivity mechanisms using scanning photocurrent imaging.

Main Results:

• The orientation-perpendicular BP homojunction exhibits good gate-tunable diode-like rectification characteristics.
• The device demonstrates polarization-sensitive properties linked to linear dichroism and anisotropic carrier transport.
• Scanning photocurrent images confirm the unique mechanisms of polarization sensitivity.

Conclusions:

• This work introduces a novel approach to engineer carrier transport anisotropy in 2D materials.
• The developed BP homojunction paves the way for next-generation electronic and optoelectronic devices.
• The findings highlight the potential of 2D anisotropic materials for advanced applications.