GHz bandwidth electro-optics of a single self-assembled quantum dot in a charge-tunable device

TL;DR

This paper demonstrates GHz bandwidth electrical control of a single quantum dot embedded in a charge-tunable device, with response times around 1 nanosecond, using innovative optical detection methods.

Contribution

It introduces a novel optical detection technique to map voltage pulses on a quantum dot, enabling GHz bandwidth electrical control in a charge-tunable device.

Findings

Quantum dot response times of ~1 ns measured

Successful GHz bandwidth electrical control demonstrated

Novel optical detection method developed

Abstract

The response of a single InGaAs quantum dot, embedded in a miniaturized charge-tunable device, to an applied GHz bandwidth electrical pulse is investigated via its optical response. Quantum dot response times of 1.0 \pm 0.1 ns are characterized via several different measurement techniques, demonstrating GHz bandwidth electrical control. Furthermore a novel optical detection technique based on resonant electron-hole pair generation in the hybridization region is used to map fully the voltage pulse experienced by the quantum dot, showing in this case a simple exponential rise.