Tuning the onset voltage of resonant tunneling through InAs quantum dots by growth parameters

TL;DR

This study explores how growth parameters influence the onset voltage of resonant tunneling in InAs quantum dots, revealing a systematic decrease linked to quantum dot size, confirmed by microscopy and photoluminescence.

Contribution

It demonstrates the relationship between InAs coverage, quantum dot size, and tunneling onset voltage, providing insights for tuning electronic properties in quantum dot devices.

Findings

Onset voltage decreases from 200 mV to 0 with increased InAs coverage.

Resonant tunneling steps are linked to quantum dot ground states.

Size-dependent effects confirmed by microscopy and photoluminescence.

Abstract

We investigated the size dependence of the ground state energy in self-assembled InAs quantum dots embedded in resonant tunneling diodes. Individual current steps observed in the current-voltage characteristics are attributed to resonant single-electron tunneling via the ground state of individual InAs quantum dots. The onset voltage of the first step observed is shown to decrease systematically from 200 mV to 0 with increasing InAs coverage. We relate this to a coverage-dependent size of InAs dots grown on AlAs. The results are confirmed by atomic force micrographs and photoluminescence experiments on reference samples.