Spectroscopy and level detuning of few-electron spin states in parallel InAs quantum dots

Abstract

We use tunneling spectroscopy to study the evolution of few-electron spin states in parallel InAs nanowire double quantum dots (QDs) as a function of level detuning and applied magnetic field. Compared to the much more studied serial configuration, parallel coupling of the QDs to source and drain greatly expands the probing range of excited state transport. Owing to a strong confinement, we can here isolate transport involving only the very first interacting single QD orbital pair. For the (2,0)-(1,1) charge transition, with relevance for spin-based qubits, we investigate the excited (1,1) triplet, and hybridization of the (2,0) and (1,1) singlets. An applied magnetic field splits the (1,1) triplet, and due to spin-orbit induced mixing with the (2,0) singlet, we clearly resolve transport through all triplet states near the avoided singlet-triplet crossings. Transport calculations, based on a simple model with one orbital on each QD, fully replicate the experimental data. Finally, we observe an expected mirrored symmetry between the 1-2 and 2-3 electron transitions resulting from the two-fold spin degeneracy of the orbitals.

arXiv comment17 pages, 8 figures

References in corpus (16)

• Quantum Computation with Quantum Dots
• Signatures of Majorana fermions in hybrid superconductor-semiconductor nanowire devices
• Spins in few-electron quantum dots
• Spin-orbit qubit in a semiconductor nanowire
• Triplet-Singlet Spin Relaxation via Nuclei in a Double Quantum Dot
• Excitation Spectra of Circular Few-Electron Quantum Dots
• Few-Electron Quantum Dot Circuit with Integrated Charge Read-Out
• Spectroscopy of spin-orbit quantum bits in indium antimonide nanowires
• Disentangling the effects of spin-orbit and hyperfine interactions on spin blockade
• Giant fluctuations and gate control of the g-factor in InAs Nanowire Quantum Dots
• Singlet-triplet splitting in double quantum dots due to spin orbit and hyperfine interactions
• Spin state mixing in InAs double quantum dots
• Carbon nanotubes for coherent spintronic devices
• Single-electron transport in InAs nanowire quantum dots formed by crystal phase engineering
• Electron-hole interactions in coupled InAs-GaSb quantum dots based on nanowire crystal phase templates
• Tuning the two-electron hybridization and spin states in parallel-coupled InAs quantum dots

Cited by in corpus (4)

• Electrical control of spins and giant g-factors in ring-like coupled quantum dots
• Josephson current via spin and orbital states of a tunable double quantum dot
• Symmetry-controlled singlet-triplet transition in a double-barrier quantum ring
• Selective tuning of spin-orbital Kondo contributions in parallel-coupled quantum dots