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.

5 Pages, 4 Figures

References in corpus (8)

• 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
• Fast Single-Charge Sensing with an rf Quantum Point Contact
• 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
• Excited states in bilayer graphene 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