Brataas, ArneRashba, Emmanuel2016-01-112012Brataas, Arne, and Emmanuel I. Rashba. 2012. “Dynamical Self-Quenching of Spin Pumping into Double Quantum Dots.” Physical Review Letters 109 (23) (December 4). doi:10.1103/physrevlett.109.236803.0031-9007http://nrs.harvard.edu/urn-3:HUL.InstRepos:24082047Nuclear spin polarization can be pumped into spin-blockaded quantum dots by multiple Landau-Zener passages through singlet-triplet anticrossings. By numerical simulations of realistic systems with 107 nuclear spins during 105 sweeps, we uncover a mechanism of dynamical self-quenching which results in a fast saturation of the nuclear polarization under stationary pumping. This is caused by screening the random field of the nuclear spins. For moderate spin-orbit coupling, self-quenching persists but its patterns are modified. Our finding explains low polarization levels achieved experimentally and calls for developing new protocols that break the self-quenching limitations.en-USJournal Article2015-12-18Arne Brataas and Emmanuel I. Rashba2016-01-1110.1103/physrevlett.109.236803