Scalable gate architecture for densely packed semiconductor spin qubits

Abstract

We demonstrate a 12 quantum dot device fabricated on an undoped Si/SiGe heterostructure as a proof-of-concept for a scalable, linear gate architecture for semiconductor quantum dots. The device consists of 9 quantum dots in a linear array and 3 single quantum dot charge sensors. We show reproducible single quantum dot charging and orbital energies, with standard deviations less than 20% relative to the mean across the 9 dot array. The single quantum dot charge sensors have a charge sensitivity of 8.2 x 10^{-4} e/root(Hz) and allow the investigation of real-time charge dynamics. As a demonstration of the versatility of this device, we use single-shot readout to measure a spin relaxation time T1 = 170 ms at a magnetic field B = 1 T. By reconfiguring the device, we form two capacitively coupled double quantum dots and extract a mutual charging energy of 200 microeV, which indicates that 50 GHz two-qubit gate operation speeds are feasible.

References in corpus (12)

• Single-shot read-out of an individual electron spin in a quantum dot
• An addressable quantum dot qubit with fault-tolerant control fidelity
• Electrically driven single electron spin resonance in a slanting Zeeman field
• Demonstration of Entanglement of Electrostatically Coupled Singlet-Triplet Qubits
• Fast Single-Charge Sensing with an rf Quantum Point Contact
• A Reconfigurable Gate Architecture for Si/SiGe Quantum Dots
• Electron counting in quantum dots
• Excited-state spectroscopy on a nearly-closed quantum dot via charge detection
• Measurement of valley splitting in high-symmetry Si/SiGe quantum dots
• Orbital and valley state spectra of a few-electron silicon quantum dot
• Enhancement-mode buried strained silicon channel quantum dot with tunable lateral geometry
• Si/SiGe quantum dot with superconducting single-electron transistor charge sensor

Cited by in corpus (4)

• Experimental Comparison of Two Quantum Computing Architectures
• Strong Coupling of a Single Electron in Silicon to a Microwave Photon
• Circuit Quantum Electrodynamics Architecture for Gate-Defined Quantum Dots in Silicon
• Entanglement entropy scaling in solid-state spin arrays via capacitance measurements