Dispersive sensing of charge states in a bilayer graphene quantum dot

Abstract

We demonstrate dispersive readout of individual charge states in a gate-defined few-electron quantum dot in bilayer graphene. We employ a radio frequency reflectometry circuit, where an LC resonator with a resonance frequency close to 280 MHz is directly coupled to an ohmic contact of the quantum dot device. The detection scheme based on changes in the quantum capacitance operates over a wide gate-voltage range and allows to probe excited states down to the single-electron regime. Crucially, the presented sensing technique avoids the use of an additional, capacitively coupled quantum device such as a quantum point contact or single electron transistor, making dispersive sensing particularly interesting for gate-defined graphene quantum dots.

arXiv comment5 Pages, 4 Figures

References in corpus (31)

• Single-shot read-out of an individual electron spin in a quantum dot
• Asymmetry gap in the electronic band structure of bilayer graphene
• Spin qubits in graphene quantum dots
• A >99.9%-fidelity quantum-dot spin qubit with coherence limited by charge noise
• A programmable two-qubit quantum processor in silicon
• Quantum CNOT Gate for Spins in Silicon
• Few-Electron Quantum Dot Circuit with Integrated Charge Read-Out
• Fast Single-Charge Sensing with an rf Quantum Point Contact
• Dispersive Readout of a Few-Electron Double Quantum Dot with Fast rf Gate-Sensors
• Fast sensing of double-dot charge arrangement and spin state with an rf sensor quantum dot
• A high-sensitivity gate-based charge sensor in silicon
• Rapid high-fidelity gate-based spin read-out in silicon
• Frequency-selective single photon detection using a double quantum dot
• Gate-based single-shot readout of spins in silicon
• Charge and spin state readout of a double quantum dot coupled to a resonator
• Spin and Valley States in Gate-defined Bilayer Graphene Quantum Dots
• Electrostatically induced quantum point contact in bilayer graphene
• Frequency Multiplexing for Readout of Spin Qubits
• Coupled quantum dots in bilayer graphene
• Excited states in bilayer graphene quantum dots
• Single-shot measurement of triplet-singlet relaxation in a Si/SiGe double quantum dot
• Gate-defined electron-hole double dots in bilayer graphene
• Measuring the complex admittance of a carbon nanotube double quantum dot
• Electron-hole crossover in gate-controlled bilayer graphene quantum dots
• 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
• Limitations to Carrier Mobility and Phase-Coherent Transport in Bilayer Graphene
• Fast charge sensing of Si/SiGe quantum dots via a high-frequency accumulation gate
• High-fidelity and robust two-qubit gates for quantum-dot spin qubits in silicon
• Electrostatic detection of Shubnikov-de-Haas oscillations in bilayer graphene by Coulomb resonances in gate-defined quantum dots

Cited by in corpus (13)

• Nanomaterials for Quantum Information Science and Engineering
• Spin relaxation in a single-electron graphene quantum dot
• Particle-hole symmetry protects spin-valley blockade in graphene quantum dots
• Gate-Controlled Quantum Dots Based on Two-Dimensional Materials
• Coherent Charge Oscillations in a Bilayer Graphene Double Quantum Dot
• Radio-frequency reflectometry in bilayer graphene devices utilizing micro graphite back-gates
• Extended Hubbard model describing small multi-dot arrays in bilayer graphene
• Tunable p-n junction barriers in few-electron bilayer graphene quantum dots
• Dipole coupling of a bilayer graphene quantum dot to a high-impedance microwave resonator
• Wide dynamic range charge sensor operation by high-speed feedback control of radio-frequency reflectometry
• Tuning confined states and valley g-factors by quantum dot design in bilayer graphene
• RFSoC-based radio-frequency reflectometry in gate-defined bilayer graphene quantum devices
• Radio-frequency charge detection on graphene electron-hole double quantum dots