Sensing dot with high output swing for scalable baseband readout of spin qubits

Abstract

A crucial requirement for quantum computing, in particular for scalable quantum computing and error correction, is a fast and high-fidelity qubit readout. For semiconductor based qubits, one limiting factor for local low-power signal amplification, is the output swing of the charge sensor. We demonstrate GaAs and Si/SiGe asymmetric sensing dots (ASDs) specifically designed to provide a significantly improved response compared to conventional charge sensing dots. Our ASD design features a strongly decoupled drain reservoir from the sensor dot, which mitigates negative feedback effects found in conventional sensors. This results in a boosted output swing of $3\text{mV}$, which exceeds the response in the conventional regime of our device by more than ten times. The enhanced output signal paves the way for employing very low-power readout amplifiers in close proximity to the qubit.

arXiv comment9 pages, 8 figures

References in corpus (28)

• Spins in few-electron quantum dots
• Few-Electron Quantum Dot Circuit with Integrated Charge Read-Out
• Two-qubit silicon quantum processor with operation fidelity exceeding 99%
• Cryogenic Control Architecture for Large-Scale Quantum Computing
• Fast Single-Charge Sensing with an rf Quantum Point Contact
• A Crossbar Network for Silicon Quantum Dot Qubits
• Singlet-triplet spin blockade and charge sensing in a few-electron double quantum dot
• Dispersive Readout of a Few-Electron Double Quantum Dot with Fast rf Gate-Sensors
• Rapid high-fidelity gate-based spin read-out in silicon
• Gate-based single-shot readout of spins in silicon
• Frequency Multiplexing for Readout of Spin Qubits
• Conveyor-mode single-electron shuttling in Si/SiGe for a scalable quantum computing architecture
• On-Chip Microwave Quantum Hall Circulator
• Spiderweb array: A sparse spin-qubit array
• Closed-loop control of a GaAs-based singlet-triplet spin qubit with 99.5% gate fidelity and low leakage
• High-fidelity single-shot readout for a spin qubit via an enhanced latching mechanism
• Blueprint of a scalable spin qubit shuttle device for coherent mid-range qubit transfer in disordered Si/SiGe/SiO${}_2$
• A cryogenic amplifier for fast real-time detection of single-electron tunneling
• The SpinBus Architecture: Scaling Spin Qubits with Electron Shuttling
• Quantum interference and phonon-mediated back-action in lateral quantum dot circuits
• Si/SiGe QuBus for single electron information-processing devices with memory and micron-scale connectivity function
• Enhanced charge detection of spin qubit readout via an intermediate state
• Spin-EPR-pair separation by conveyor-mode single electron shuttling in Si/SiGe
• Phonon-mediated vs. Coulombic Back-Action in Quantum Dot circuits
• Few electron double quantum dot in an isotopically purified ${}^{28}$Si quantum well
• Mapping of valley-splitting by conveyor-mode spin-coherent electron shuttling
• Conditional dispersive readout of a CMOS quantum dot via an integrated transistor circuit
• Tailoring potentials by simulation-aided design of gate layouts for spin qubit applications

Cited by in corpus (4)

• Conveyor-mode single-electron shuttling in Si/SiGe for a scalable quantum computing architecture
• The SpinBus Architecture: Scaling Spin Qubits with Electron Shuttling
• Spin-EPR-pair separation by conveyor-mode single electron shuttling in Si/SiGe
• Atomistic compositional details and their importance for spin qubits in isotope-purified silicon-germanium quantum wells