The engineering of electron spin qubits in a compact unit cell embedding all quantum functionalities is mandatory for large scale integration. In particular, the development of a high-fidelity and scalable spin readout method remains an open challenge. Here we demonstrate high-fidelity and robust spin readout based on gate reflectometry in a CMOS device comprising one qubit dot and one ancillary dot coupled to an electron reservoir to perform readout. This scalable method allows us to read out a spin with a fidelity above 99% for 1 ms integration time. To achieve such fidelity, we exploit a latched spin blockade mechanism that requires electron exchange between the ancillary dot and the reservoir. We show that the demonstrated high read-out fidelity is fully preserved up to 0.5 K. This results holds particular relevance for the future co-integration of spin qubits and classical control electronics.
@article{arxiv.1809.04584,
title = {Gate-Based High Fidelity Spin Read-out in a CMOS Device},
author = {Matias Urdampilleta and David J. Niegemann and Emmanuel Chanrion and Baptiste Jadot and Cameron Spence and Pierre-André Mortemousque and 1 Christopher Bäuerle and Louis Hutin and Benoit Bertrand and Sylvain Barraud and Romain Maurand and Marc Sanquer and Xavier Jehl and Silvano De Franceschi and Maud Vinet and Tristan Meunier},
journal= {arXiv preprint arXiv:1809.04584},
year = {2018}
}