There has been considerable progress in electro-statically emptying, and re-filling, quantum dots with individual electrons. Typically the quantum dot is defined by electrostatic gates on a GaAs/AlGaAs modulation doped heterostructure. We report the filling of such a quantum dot by a single photo-electron, originating from an individual photon. The electrostatic dot can be emptied and reset in a controlled fashion before the arrival of each photon. The trapped photo-electron is detected by a point contact transistor integrated adjacent to the electrostatic potential trap. Each stored photo-electron causes a persistent negative step in the transistor channel current. Such a controllable, benign, single photo-electron detector could allow for information transfer between flying photon qubits and stored electron qubits.
@article{arxiv.quant-ph/0410094,
title = {Single photo-electron trapping, storage, and detection in a one-electron quantum dot},
author = {Deepak Sethu Rao and Thomas Szkopek and Hans Daniel Robinson and Eli Yablonovitch and Hong-Wen Jiang},
journal= {arXiv preprint arXiv:quant-ph/0410094},
year = {2015}
}