Analysing quantized resistance behaviour in graphene Corbino p-n junction devices

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Graphene Corbino p-n junction devices have promising applications in quantum electronics.
• Device scalability is critical for applications like resistance metrology, requiring microampere current compatibility.
• Fabrication of high-quality graphene devices remains challenging.

Purpose of the Study:

• To investigate and characterize unusual quantized resistances in epitaxial graphene Corbino p-n junction devices.
• To explore the potential of ultraviolet lithography for scaling graphene device fabrication.
• To develop empirical formulae for describing observed quantized resistances and edge channel behavior.

Main Methods:

• Experimental observation of quantized resistances in graphene Corbino p-n junction devices at the ν = 2 plateau.
• Numerical simulations using the LTspice circuit simulator to model device behavior.
• Empirical derivation of formulae to describe experimental and simulated data with generalized current terminal placement.

Main Results:

• Unusual quantized resistances were observed and agreed with LTspice simulations.
• An empirical formula was derived to describe quantized resistances for up to three current terminals.
• Partial edge channel cancellation was accurately reflected in the derived formulae.

Conclusions:

• The findings support the use of ultraviolet lithography for scalable fabrication of graphene devices.
• Narrow junctions in graphene Corbino devices are suitable for various subfields.
• The observed quantized resistances and developed formulae advance the understanding and application of graphene electronics.