Dynamically controlled charge sensing of a few-electron silicon quantum dot

TL;DR

This paper demonstrates a dynamically controlled charge sensing method for silicon quantum dots using a single-electron transistor with feedback, enabling precise detection of single-electron occupancy despite charge noise.

Contribution

It introduces a digitally-controlled feedback technique for charge sensing in silicon quantum dots, improving robustness and sensitivity over previous static methods.

Findings

Sensitive detection of quantum dot charge states achieved

Robust operation despite charge drifts and rearrangements

Single-electron occupancy can be reliably probed

Abstract

We report charge sensing measurements of a silicon metal-oxide-semiconductor quantum dot using a single-electron transistor as a charge sensor with dynamic feedback control. Using digitallycontrolled feedback, the sensor exhibits sensitive and robust detection of the charge state of the quantum dot, even in the presence of charge drifts and random charge rearrangements. The sensor enables the occupancy of the quantum dot to be probed down to the single electron level.