Repeated measurements and nuclear spin polarization

TL;DR

This paper explores how repeated, noncontinuous measurements of electron spins in quantum dots can induce and manipulate nuclear spin polarization, offering a new approach complementary to existing methods.

Contribution

It introduces a measurement-based technique for nuclear spin polarization that deforms nuclear wave functions and acts as a control mechanism, expanding current spin manipulation strategies.

Findings

Measurement techniques can induce nuclear spin polarization.

Repeated measurements deform nuclear wave functions.

Method can serve as a nuclear spin control gate.

Abstract

We study repeated (noncontinuous) measurements on the electron spin in a quantum dot and find that the measurement technique may lead to a different met$ or mechanism to realize nuclear spin polarization. While it may be used in any case, the method is aimed at the further polarization, providing that nuclear spins have been polarized by the existent electrical or optical methods. The feasibility of the method is analyzed. The existing techniques in electron spin measurements are applicable to this scheme. The repeated measurements \emph{deform} the structures of the nuclear wave function and can also serve as $\emph{gates}$ to manipulate nuclear spins.