2012/09/13 by Mark S. Rudner, M. S. Rudner, Leonid Levitov +1 · 8 citations
Physics and Astronomy · #Amplitude #Condensed matter physics #Electron #Magnetic field #Magnetic properties of thin films #Oscillation (cell signaling) #Physics #Polarization (electrochemistry) #Quantum #Quantum and electron transport phenomena #Quantum dot #Quantum mechanics #Quantum tunnelling #Semiconductor Quantum Structures and Devices #cond-mat.mes-hall
paper · pdf · doi:10.1103/physrevlett.110.086601
published in Physical Review Letters 110(8), 086601 (American Physical Society)
arxiv created 2012/09/13 · openalex publication_date 2013/02/20 · arxiv updated 2013/05/02 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Early experiments on spin-blockaded double quantum dots revealed robust, large-amplitude current oscillations in the presence of a static (dc) source-drain bias. Despite experimental evidence implicating dynamical nuclear polarization, the mechanism has remained a mystery. Here we introduce a minimal albeit realistic model of coupled electron and nuclear spin dynamics which supports self-sustained oscillations. Our mechanism relies on a nuclear spin analog of the tunneling magnetoresistance phenomenon (spin-dependent tunneling rates in the presence of an inhomogeneous Overhauser field) and nuclear spin diffusion, which governs dynamics of the spatial profile of nuclear polarization. The proposed framework naturally explains the differences in phenomenology between vertical and lateral quantum dot structures as well as the extremely long oscillation periods.