Engineering single donor detectors in doped silicon

TL;DR

This paper demonstrates engineering single donor transistors in doped silicon by exploiting glassy behavior and electron dynamics, enabling charge detection and control at the single-donor level.

Contribution

It introduces a method to create and characterize single donor transistors in doped silicon using intrinsic material properties and capacitance simulations.

Findings

Single donors can be electrostatically isolated near tunnel barriers.

Charge stability diagrams of coupled quantum dots are observable.

Capacitance-based models support the experimental results.

Abstract

We demonstrate the possibility of engineering a single donor transistor directly from a phosphorous doped quantum dot by making use of the intrinsic glassy behaviour of the structure as well as the complex electron dynamics during cooldown. Characterisation of the device at low temperatures and in magnetic field shows single donors can be electrostatically isolated near one of the tunnel barrier with either a single or a doubly occupancy. Such a model is well supported by capacitance-based simulations. Ability of using the D0 of such isolated donor as a charge detector is demonstrated by observing the charge stability diagram of a nearby and capacitively coupled semi-connected double quantum dot.