Current-Induced Cooling of Nuclear Spins in Quantum Dots

Mark Rudner, MIT

Abstract: Due to the coupling of electron and nuclear spins in quantum dots, uncertainty in the nuclear spin state leads to undesirable effects in electron spin dynamics such as dephasing and fluctuations in Zeeman energy. Learning how to control nuclear spins in such systems will thus both increase our possibilities for nuclear spin-based information storage and manipulation, and our ability to coherently control the behavior of electron spins. In this talk, I will cover some background of the interesting physics of spin-blockade, and present a model of transport in this regime in which internal feedback produces a squeezing effect on the nuclear spin distribution. By tuning to this regime, we estimate that the width of the nuclear spin distribution can be reduced by more than a factor of 10.