Singlet-triplet transition in a few-electron lateral InGaAs-InAlAs quantum dot

TL;DR

This paper investigates the magnetic-field-induced singlet-triplet transition in a few-electron lateral InGaAs-InAlAs quantum dot, providing insights into spin state manipulation relevant for quantum information processing.

Contribution

It reports the first observation of a singlet-triplet transition in a lateral InGaAs-InAlAs quantum dot and measures the gyromagnetic factor in this system.

Findings

Singlet-triplet transition occurs at 0.7 T magnetic field.

Gyromagnetic factor of 4.4 measured.

Potential for spin state control in quantum computing.

Abstract

The magnetic-field evolution of Coulomb blockade peaks in lateral InGaAs/InAlAs quantum dots in the few-electron regime is reported. Quantum dots are defined by gates evaporated onto a 60 nm-thick hydrogen silsesquioxane insulating film. A gyromagnetic factor of 4.4 is measured via zero-bias spin spectroscopy and a transition from singlet to triplet spin configuration is found at an in-plane magnetic field B = 0.7 T. This observation opens the way to the manipulation of singlet and triplet states at moderate fields and its relevance for quantum information applications will be discussed.