TY - JOUR

T1 - Theory of coherent dynamic nuclear polarization in quantum dots

AU - Neder, Izhar

AU - Rudner, Mark Spencer

AU - Halperin, Bertrand

PY - 2014/2/4

Y1 - 2014/2/4

N2 - We consider the production of dynamic nuclear spin polarization (DNP) in a two-electron double quantum dot, in which the electronic levels are repeatedly swept through a singlet-triplet avoided crossing. Our analysis helps to elucidate the intriguing interplay between electron-nuclear hyperfine coupling, electronic spin-orbit coupling, and electron and nuclear Larmor precession in an externally- applied magnetic field, in guiding the production of DNP. In particular, we specifically address the roles of multiple nuclear spin species. By treating the nuclear spin dynamics semi-classically, we identify two contributions to the DNP production rate, a “geometric contribution” and a “dynamic contribution,” which depend in very different ways on control parameters such as the sweep rate and holding time near the level crossing. We find that the dynamical contribution dominates the DNP when the system is held near the singlet-triplet avoided crossing for a time on the order of the nuclear Larmor period. Detailed numerical calculations provide a physical picture for understanding the oscillations observed by Foletti et. al. in arXiv:0801.3613.

AB - We consider the production of dynamic nuclear spin polarization (DNP) in a two-electron double quantum dot, in which the electronic levels are repeatedly swept through a singlet-triplet avoided crossing. Our analysis helps to elucidate the intriguing interplay between electron-nuclear hyperfine coupling, electronic spin-orbit coupling, and electron and nuclear Larmor precession in an externally- applied magnetic field, in guiding the production of DNP. In particular, we specifically address the roles of multiple nuclear spin species. By treating the nuclear spin dynamics semi-classically, we identify two contributions to the DNP production rate, a “geometric contribution” and a “dynamic contribution,” which depend in very different ways on control parameters such as the sweep rate and holding time near the level crossing. We find that the dynamical contribution dominates the DNP when the system is held near the singlet-triplet avoided crossing for a time on the order of the nuclear Larmor period. Detailed numerical calculations provide a physical picture for understanding the oscillations observed by Foletti et. al. in arXiv:0801.3613.

U2 - 10.1103/PhysRevB.89.085403

DO - 10.1103/PhysRevB.89.085403

M3 - Journal article

VL - 89

JO - Physical Review B

JF - Physical Review B

SN - 2469-9950

IS - 8

M1 - 085403

ER -