Nanometer-Scale Lateral p-n Junctions in Graphene/α-RuCl₃ Heterostructures

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Nanometer-scale lateral p-n junctions are critical for next-generation two-dimensional (2D) electronic devices.
• Existing methods for creating such junctions face challenges in precision and scalability.

Purpose of the Study:

• To realize and characterize nanoscale lateral p-n junctions in 2D materials.
• To investigate the electronic and optical properties of these junctions.
• To provide a foundation for fabricating advanced 2D electronic devices.

Main Methods:

• Utilized the graphene/α-RuCl3 charge-transfer heterostructure.
• Employed scanning tunneling microscopy (STM) and spectroscopy (STS) to probe electronic properties.
• Used scattering-type scanning near-field optical microscopy (s-SNOM) for optical response analysis.
• Performed ab initio density functional theory (DFT) calculations for theoretical validation.

Main Results:

• Successfully created nanoscale lateral p-n junctions with widths of approximately 3 nm.
• Achieved a band offset of ~0.6 eV, generating electric fields of ~10^8 V/m.
• Validated a point-scatterer model for surface plasmon polariton (SPP) interactions with nanobubbles.
• DFT calculations confirmed experimental findings and revealed charge transfer dependence on layer separation.

Conclusions:

• Demonstrated the feasibility of creating high-quality nanoscale lateral p-n junctions in 2D materials.
• Established experimental and conceptual frameworks for the design and fabrication of 2D p-n nanojunctions.
• The findings pave the way for novel 2D device architectures and functionalities.