2008/01/23 by Sandra Foletti, J. Martin, Foletti, S. +9
Physics and Astronomy · #Advanced Chemical Physics Studies #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall) #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena
paper · pdf · doi:10.48550/arxiv.0801.3613
openalex publication_date 2008/01/23 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We observe dynamic nuclear polarization in a GaAs double dot system using two electrons that are never exchanged with the reservoir. By periodically bringing the system to the mixing point where the singlet and the triplet T+ states are degenerate, we observe that an excess polarization is built up. Surprisingly, the pumping procedure is most effective when the total duty cycle equals a multiple of the Larmor precession time of the Ga and As nuclei. The induced polarization corresponds to cooling of the underlying nuclear system. The dependence on the dwell time at the mixing point is found to be non-monotonic.