Magnetic tuning of tunnel coupling between InAsP double quantum dots in InP nanowires

TL;DR

This paper investigates how in-plane magnetic fields can be used to tune the tunnel coupling between InAsP double quantum dots in InP nanowires, combining experimental and theoretical approaches to control quantum dot interactions.

Contribution

It demonstrates magnetic field control of interdot coupling in InAsP quantum dot molecules grown in nanowires, advancing quantum qubit development.

Findings

Magnetic field can modulate interdot tunneling strength.

Sample geometry influences tunneling control.

Magnetic tuning enables in-situ coupling adjustment.

Abstract

We study experimentally and theoretically the in-plane magnetic field dependence of the coupling between dots forming a vertically stacked double dot molecule. The InAsP molecule is grown epitaxially in an InP nanowire and interrogated optically at millikelvin temperatures. The strength of interdot tunneling, leading to the formation of the bonding-antibonding pair of molecular orbitals, is investigated by adjusting the sample geometry. For specific geometries, we show that the interdot coupling can be controlled in-situ using a magnetic field-mediated redistribution of interdot coupling strengths. This is an important milestone in the development of qubits required in future quantum information technologies.