Voltage-Tunable Nonlocal Metasurface for Enhanced Outcoupling of Emission from Quantum Dots

TL;DR

A metasurface platform with quantum dots is developed to enhance photon emission for quantum information processing.

Contribution

A nonlocal metasurface platform is introduced that enables tunable emission and improved outcoupling from distant quantum dots.

Findings

GaAs quantum dots in a nonlocal metasurface produce same-wavelength photons with enhanced outcoupling efficiency.

The metasurface's design eliminates the need for precise quantum dot placement.

Spectral alignment of quantum dots is achieved through natural dipole moment variation.

Abstract

Cooperative emission of indistinguishable
photons from multiple
distant sources can enable quantum information processing, and low-density
semiconductor quantum dots (QDs) embedded in metasurfaces hold promise
to scale up this functionality. However, the inhomogeneity in size
within QD ensembles and limited interresonator coupling in local metasurfaces
make this effect highly unlikely. Here, we demonstrate a nonlocal
metasurface platform with embedded GaAs QDs coupled to extended photonic
modes with emission wavelength tunability and enhanced free-space
emission outcoupling. Natural variation in the QD dipole moment allows
us to tune two QDs into spectral alignment and resonance with selected
modes. As a result, two distant QDs can produce same-wavelength photons
with strongly improved outcoupling efficiency to free space. The nonlocal
and periodic nature of the developed metasurface eliminates the need
for precise placement of individual QDs and, although cooperative
emission was not yet demonstrated, this metasurface platform opens
doors for investigations of cooperative effects for quantum information
system applications.

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