Bright Quantum Dot Single-Photon Emitters at Telecom Bands Heterogeneously Integrated on Si

Area of Science:

• Quantum Information Science
• Materials Science
• Nanotechnology

Background:

• Silicon photonics is ideal for scalable quantum information processing but lacks efficient photon sources.
• Semiconductor quantum dots (QDs) emit photons in telecom bands and are compatible with silicon integration.

Purpose of the Study:

• To develop a novel, robust, and industry-compatible method for single-photon emission from InAs/InP QDs heterogeneously integrated with silicon.
• To demonstrate a proof-of-concept device for efficient photon generation and high-purity single-photon emission.

Main Methods:

• Heterogeneous integration of Indium Arsenide/Indium Phosphide quantum dots (QDs) onto a silicon substrate.
• Fabrication of a vertical emitting device incorporating a metallic mirror beneath the QD emitter.
• Characterization of single-photon purity using the second-order correlation function (g(2)(τ = 0)).

Main Results:

• Achieved photon extraction efficiencies of approximately 10% from the QD emitters.
• Demonstrated high-purity single-photon generation with g(2)(τ = 0) < 0.02 under continuous wave excitation.
• Maintained high-purity single-photon emission up to 50 K and achieved g(2)(0) down to 0.205 ± 0.020 for pulsed excitation.

Conclusions:

• The developed approach is novel, robust, and industry-compatible for single-photon generation using QDs on silicon.
• The fabricated devices show competitive performance compared to existing methods, enabling practical quantum information processing applications.
• This work paves the way for scalable quantum technologies leveraging heterogeneous integration of quantum dots with silicon photonics.