Finite bias charge detection in a quantum dot

TL;DR

This paper demonstrates finite bias measurements on a quantum dot coupled to a quantum point contact, enabling charge detection and analysis of coupling to leads in the non-blockaded regime.

Contribution

It introduces a method to measure the time-averaged charge and coupling in a quantum dot using a quantum point contact at finite bias.

Findings

Determined the time-averaged charge on the quantum dot.

Estimated the coupling strength between the dot and leads.

Identified structure in the transconductance signal at finite bias.

Abstract

We present finite bias measurements on a quantum dot coupled capacitively to a quantum point contact used as a charge detector. The transconductance signal measured in the quantum point contact at finite dot bias shows structure which allows us to determine the time-averaged charge on the dot in the non-blockaded regime and to estimate the coupling of the dot to the leads.