Probing a Single Nuclear Spin in a Silicon Single Electron Transistor

TL;DR

This paper investigates how a single bismuth nuclear spin influences electron transport in a silicon nanotransistor, revealing hyperfine effects and nuclear spin polarization at very low temperatures.

Contribution

It demonstrates the impact of hyperfine coupling on transport characteristics and shows nuclear spin polarization control via bias tuning in a silicon-based device.

Findings

Hyperfine splitting observed in dI/dV curves at 100 mK.

Nuclear spins can be partially polarized by bias tuning.

Transport characteristics reflect hyperfine interactions and magnetic field effects.

Abstract

We study single electron transport across a single Bi dopant in a Silicon Nanotransistor to assess how the strong hyperfine coupling with the Bi nuclear spin $I=9/2$ affects the transport characteristics of the device. In the sequential tunneling regime we find that at, temperatures in the range of $100 mK$, $dI/dV$ curves reflect the zero field hyperfine splitting as well as its evolution under an applied magnetic field. Our non-equilibrium quantum simulations show that nuclear spins can be partially polarized parallel or antiparallel to the electronic spin just tuning the applied bias.