# Electrical single spin read-out using an exchange-coupled quantum dot

## TL;DR

This paper introduces a novel all-electrical, non-destructive method for continuous single spin detection using exchange interaction with a quantum dot, achieving high fidelity and significant conductance changes.

## Contribution

It demonstrates a new exchange-coupled quantum dot technique for single spin read-out, offering an alternative to spin-charge conversion methods.

## Key findings

- Conductance variations up to 4% observed.
- Read-out fidelities exceed 99.5%.
- Asymmetric exchange coupling model matches experimental data.

## Abstract

We present a new way of continuously reading-out the state of a single electronic spin. Our detection scheme is based on an exchange interaction between the electronic spin and a nearby read-out quantum dot. The coupling between the two systems results in a spin-dependent conductance through the read-out dot and establishes an all electrical and non-destructive single spin detection. With conductance variations up to 4% and read-out fidelities greater than 99.5%, this method represents an alternative to systems where spin to charge conversion cannot be implemented. Using a semi-classical approach, we present an asymetric exchange coupling model in good agreement with our experimental results.