2017/06/03 by Frederico Martins, Filip K. Malinowski, Peter D. Nissen +6 · 1 citation
Physics and Astronomy · #Atomic physics #Condensed matter physics #Magnetic properties of thin films #Physics #Quantum and electron transport phenomena #Quantum dot #Quantum mechanics #Semiconductor Quantum Structures and Devices #Spin (aerodynamics) #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevlett.119.227701
published as Phys. Rev. Lett. 119, 227701 (2017) · 8 pages, including 4 main figures and 2 supplementary figurures
arxiv created 2017/06/03 · openalex publication_date 2017/11/30 · arxiv updated 2017/12/06 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We use a one-electron quantum dot as a spectroscopic probe to study the spin properties of a gate-controlled multielectron GaAs quantum dot at the transition between odd and even occupation numbers. We observe that the multielectron ground-state transitions from spin-1/2-like to singletlike to tripletlike as we increase the detuning towards the next higher charge state. The sign reversal in the inferred exchange energy persists at zero magnetic field, and the exchange strength is tunable by gate voltages and in-plane magnetic fields. Complementing spin leakage spectroscopy data, the inspection of coherent multielectron spin exchange oscillations provides further evidence for the sign reversal and, inferentially, for the importance of nontrivial multielectron spin exchange correlations.