Efficient Generation of Entangled Photons in the Telecommunications Range Using Nonlinear Metasurfaces Integrated With ScAlN/GaN Heterostructures

Abstract

ABSTRACT Entangled photons provide non‐classical correlations that enable measurement sensitivities beyond classical limits, scalable fault‐tolerant quantum computation, and fundamentally secure quantum communication, making them a foundational necessity for next‐generation quantum technologies. Here we propose and analyze a novel source of entangled photons based on ScAlN/GaN quantum wells integrated with dielectric metasurfaces. Giant second‐order intersubband nonlinearity of the GaN quantum wells with strain‐compensated delta‐doped ScAlN barriers caused by strong built‐in electric fields combined with superior mode‐coupling performance of metasurfaces optimized by inverse design give rise to efficient parametric down‐conversion and generation of entangled photons in the telecom range. We develop a rigorous Heisenberg–Langevin formalism which includes field quantization, dissipation and fluctuations for all fields, parametric amplification of thermal noise and zero‐point fluctuations, and other relevant effects. Our proposed approach of employing the emergent photonic material ScAlN promises high biphoton generation rate over from a compact integrated structure that is only 0.5 thick while mitigating strain‐related issues that have so far impeded progress of nitride‐based heterostructures for quantum photonic applications into the infrared and visible wavelengths. Our result therefore is relevant for numerous applications ranging from quantum sensing, quantum information, and computing.

The authors' abstract, as published at the source. Advanced Functional Materials, 2026 · DOI ↗