Valley subband splitting in bilayer graphene quantum point contact

Abstract

We report a study of one-dimensional subband splitting in a bilayer graphene quantum point contact in which quantized conductance in steps of $4e^2/h$ is clearly defined down to the lowest subband. While our source-drain bias spectroscopy measurements reveal an unconventional confinement, we observe a full lifting of the valley degeneracy at high magnetic fields perpendicular to the bilayer graphene plane for the first two lowest subbands where confinement and Coulomb interactions are the strongest and a peculiar merging/mixing of $K$ and $K^{\prime }$ valleys from two non-adjacent subbands with indices $(N,N+2)$ which are well described by our semi-phenomenological model.

References in corpus (40)

• Landau level degeneracy and quantum Hall effect in a graphite bilayer
• Valley filter and valley valve in graphene
• Gate-induced insulating state in bilayer graphene devices
• Asymmetry gap in the electronic band structure of bilayer graphene
• Quantum Transport in Semiconductor Nanostructures
• The electronic properties of bilayer graphene
• Spin qubits in graphene quantum dots
• An Electronic Mach-Zehnder Interferometer
• Possible Spin Polarization in a One-Dimensional Electron Gas
• Counting statistics of single-electron transport in a quantum dot
• Coherence and Indistinguishability of Single Electrons Emitted by Independent Sources
• Aharonov-Bohm effect and broken valley-degeneracy in graphene rings
• Fast Single-Charge Sensing with an rf Quantum Point Contact
• Controllable valley splitting in silicon quantum devices
• Gate-controlled topological conducting channels in bilayer graphene
• Conductance Quantization in Graphene Nanoribbons
• Gate Defined Quantum Confinement in Suspended Bilayer Graphene
• Bound states and magnetic field-induced valley splitting in gate-tunable graphene quantum dots
• Real-time detection of single electron tunneling using a quantum point contact
• Quantized conductance of a suspended graphene nanoconstriction
• What lurks below the last plateau: Experimental studies of the 0.7 x 2e^2/h conductance anomaly in one-dimensional systems
• Electrostatically induced quantum point contact in bilayer graphene
• Gate defined zero- and one-dimensional confinement in bilayer graphene
• Charge Distribution in a Kondo Correlated Quantum Dot
• Incipient Formation of an Electron Lattice in a Weakly-Confined Quantum Wire
• Single Shot Charge Detection Using A Radio-Frequency Quantum Point Contact
• Size quantization of Dirac fermions in graphene constrictions
• Gate-defined electron-hole double dots in bilayer graphene
• Quantized conductance in an AlAs 2D electron system quantum point contact
• Topologically non-trivial valley states in bilayer graphene quantum point contacts
• Influence of minivalleys and Berry curvature on electrostatically induced quantum wires in gapped bilayer graphene
• Anomalous Conductance Quantization in Carbon Nanotubes
• Spin-Incoherent Transport in Quantum Wires
• Tunable transmission of quantum Hall edge channels with full degeneracy lifting in split-gated graphene devices
• Magnetoelectric coupling, Berry phase, and Landau level dispersion in a biased bilayer graphene
• Tailoring supercurrent confinement in graphene bilayer weak links
• Conductance quantization in etched Si/SiGe quantum point contacts
• From diffusive to ballistic transport in etched graphene constrictions and nanoribbons
• Electron flow in split-gated bilayer graphene
• Valley splitting in a Si/SiGe quantum point contact

Cited by in corpus (33)

• Excited states in bilayer graphene quantum dots
• Electron-hole crossover in gate-controlled bilayer graphene quantum dots
• Tunable Valley Splitting due to Topological Orbital Magnetic Moment in Bilayer Graphene Quantum Point Contacts
• Single-electron double quantum dots in bilayer graphene
• Observation of the spin-orbit gap in bilayer graphene by one-dimensional ballistic transport
• Charge detection in gate-defined bilayer graphene quantum dots
• Transport spectroscopy of ultraclean tunable band gaps in bilayer graphene
• Topologically non-trivial valley states in bilayer graphene quantum point contacts
• Quartet states in two-electron quantum dots in bilayer graphene
• Quantum Hall valley splitters and tunable Mach-Zehnder interferometer in graphene
• Gate-Controlled Quantum Dots Based on Two-Dimensional Materials
• A Ballistic Graphene Cooper Pair Splitter
• Engineering of the topological magnetic moment of electrons in bilayer graphene using strain and electrical bias
• Control of Giant Topological Magnetic Moment and Valley Splitting in Trilayer Graphene
• Theory of tunneling spectra for a few-electron bilayer graphene quantum dot
• Low Magnetic Field Regime of a Gate-Defined Constriction in High-Mobility Graphene
• Valley current generation using biased bilayer graphene dots
• Electrostatic detection of Shubnikov-de-Haas oscillations in bilayer graphene by Coulomb resonances in gate-defined quantum dots
• Kagomé network of chiral miniband-edge states in double-aligned graphene-hexagonal boron nitride structures
• Specular electron focusing between gate-defined quantum point contacts in bilayer graphene
• A ballistic electron source with magnetically-controlled valley polarization in bilayer graphene
• Scattering of topological kink-antikink states in bilayer graphene structures
• Semimetallic features in quantum transport through a gate-defined point contact in bilayer graphene
• Andreev and normal reflections in gapped bilayer graphene-superconductor junctions
• Manipulating electron waves in graphene using carbon nanotube gating
• Tunable spin-orbit splitting in bilayer graphene/WSe${}_2$ quantum devices
• Geometry effects in topologically confined bilayer graphene loops
• Conductance of electrostatic wire junctions in bilayer graphene
• Large Zeeman Splitting in Out-of-Plane Magnetic Field in a Double-Layer Quantum Point Contact
• Four-band effective square lattice model for Bernal-stacked bilayer graphene
• Trivial and topological bound states in bilayer graphene quantum dots and rings
• Electrostatic tuning of bilayer graphene edge modes
• Spin-valley 0.7 anomaly in bilayer graphene/WSe${}_2$ quantum point contacts