Quasi-one-dimensional transport in graphene under a magnetic field

Examining the potential of monolayer graphene in quantum information processing, this study investigates electron transport characteristics of a ballistic graphene device featuring a quantum point contact (QPC) in a split-gate geometry for Quantum Hall (QH) interferometry. Utilizing the QPC in a split-gate geometry, we demonstrate robust control over electron transport, allowing selective transmission and reflection. Our experimental study involves careful examination of quantized conductance in a four-terminal geometry under varying magnetic fields and gate voltage, confirming the effectiveness of the QPC as an electron beam splitter. The experiment reveals quantized conductance steps in steps of 4e2/h\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$4{e}<^>{2}/h$$\end{document} in the absence and presence of a magnetic field, emphasizing stability of our quasi-1D transport channels. The tunable transmission probabilities of the QPC offer a versatile tool for manipulating electron transport, providing valuable insights for controlled quantum interferometric setups. The findings lay a foundation for future advancements in quantum information processing, opening avenues for topologically protected quantum computation.