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

Chieh-I Liu,Dominick S Scaletta,Heather M Hill,Antonio Levy,Mattias Kruskopf,Dinesh K Patel,Albert F Rigosi

doi:10.1088/1361-6463/ab83bb

Abstract

Just a few of the promising applications of graphene Corbino pnJ devices include two-dimensional Dirac fermion microscopes, custom programmable quantized resistors, and mesoscopic valley filters. In some cases, device scalability is crucial, as seen in fields like resistance metrology, where graphene devices are required to accommodate currents of the order 100 μA to be compatible with existing infrastructure. However, fabrication of these devices still poses many difficulties. In this work, unusual quantized resistances are observed in epitaxial graphene Corbino p-n junction devices held at the plateau () and agree with numerical simulations performed with the LTspice circuit simulator. The formulae describing experimental and simulated data are empirically derived for generalized placement of up to three current terminals and accurately reflect observed partial edge channel cancellation. These results support the use of ultraviolet lithography as a way to scale up graphene-based devices with suitably narrow junctions that could be applied in a variety of subfields.

Highlights

Graphene and all devices fabricated from it have been studied extensively since its discovery [1,2,3,4]
Unusual quantized resistances are observed in epitaxial graphene Corbino p-n junction devices held at the ν = 2 plateau (RH ≈ 12906 Ω) and agree with numerical simulations performed with the LTspice circuit simulator
Conventional p-n junction Hall devices may exhibit a variety of ratios of the von Klitzing constant while in the quantum Hall regime [5,6,7,8,9,10,11,12,13,14,15,16,17,18]

Summary

Introduction

Graphene and all devices fabricated from it have been studied extensively since its discovery [1,2,3,4]. Conventional p-n junction (pnJ) Hall devices may exhibit a variety of ratios of the von Klitzing constant while in the quantum Hall regime [5,6,7,8,9,10,11,12,13,14,15,16,17,18]. The first question that may come to mind regards how such devices could be applied to various problems. Applications of these Corbino pnJ devices include the possible construction of more sophisticated two-dimensional Dirac fermion microscopes that rely on large-scale junction interfaces [46], custom programmable quantized resistors [47], and mesoscopic valley filters [21]. In resistance metrology, graphene devices are required to accommodate currents of the order 10 μA and above (modern-day usage may even exceed 100 μA) in order to ensure compatibility with existing infrastructure [31, 37, 40]

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Results

Conclusion