Single-shot measurement and tunnel-rate spectroscopy of a Si/SiGe few-electron quantum dot

Abstract

We investigate the tunnel rates and energies of excited states of small numbers of electrons in a quantum dot fabricated in a Si/SiGe heterostructure. Tunnel rates for loading and unloading electrons are found to be strongly energy dependent, and they vary significantly between different excited states. We show that this phenomenon enables charge sensing measurements of the average electron occupation that are analogous to Coulomb diamonds. Excited-state energies can be read directly from the plot, and we develop a rate model that enables a quantitative understanding of the relative sizes of different electron tunnel rates.

9 pages

References in corpus (7)

• Single-shot read-out of an individual electron spin in a quantum dot
• Electrically driven single electron spin resonance in a slanting Zeeman field
• Single-shot readout of electron spin states in a quantum dot using spin-dependent tunnel rates
• Excited-state spectroscopy on a nearly-closed quantum dot via charge detection
• Single-electron quantum dot in Si/SiGe with integrated charge-sensing
• Fast tunnel rates in Si/SiGe one-electron single and double quantum dots
• Pauli spin blockade and lifetime-enhanced transport in a Si/SiGe double quantum dot

Cited by in corpus (17)

• Silicon Quantum Electronics
• Quantum Decoherence of the Central Spin in a Sparse System of Dipolar Coupled Spins
• Rapid high-fidelity spin state readout in Si/SiGe quantum dots via radio-frequency reflectometry
• High-fidelity single-shot readout for a spin qubit via an enhanced latching mechanism
• Tunable singlet-triplet splitting in a few-electron Si/SiGe quantum dot
• Disorder-induced valley-orbit hybrid states in Si quantum dots
• Two-electron dephasing in single Si and GaAs quantum dots
• Few electron double quantum dot in an isotopically purified ${}^{28}$Si quantum well
• Coherent electrical rotations of valley states in Si quantum dots using the phase of the valley-orbit coupling
• Single charge sensing and transport in double quantum dots fabricated from commercially grown Si/SiGe heterostructures
• SiGe/Si quantum dot electron spin decoherence dependence on ${}^{73}$Ge
• Identifying single electron charge sensor events using wavelet edge detection
• Characterization of a gate-defined double quantum dot in a Si/SiGe nanomembrane
• Spin Accumulation Encoded in Electronic Noise for Mesoscopic Billiards with Finite Tunneling Rates
• Spectroscopy of multi-electrode tunnel barriers
• Control of threshold voltages in Si/SiGe quantum devices via optical illumination
• Charge detection of a quantum dot under different tunneling barrier symmetries and bias voltages