Skip to Content

Deterministically separable polarization-entangled photons from battery-powered diode lasers

The development of entangled photon sources with high flux and fidelity is crucial for the future of quantum information processing. Polarization entanglement has been one of the most widely used degrees of freedom due to its ease of manipulation and state detection. Furthermore, the generation of broadband polarization-entangled photons leaves the frequency degree of freedom available for spectral multiplexing in quantum networks.

Publication Date: July 31, 2025

Authors: Zacharie M. Léger, Trevor J. Stirling, Meng Lon Iu, Amr S. Helmy

Abstract:

Large-scale integrated sources of quantum light are enabling ingredients for the future of photonic quantum technologies. For such platforms, sources based on electrical injection are of value for their turnkey operation, as they do not rely on bulky off-chip sources to achieve quantum nonlinear conversion. This work presents the first demonstration of a source of entangled photons fully contained in a single waveguide. Our source is based on a single battery-powered Bragg reflection waveguide diode laser producing two indistinguishable sources of ultra-broadband polarization-entangled photons. The output state of our device has a Bell-state fidelity of 86.3% without accidental subtraction, a high entangled pair generation rate of 1.16 × 106 (pairs)/(s ⋅ mW ⋅ facet), and an ultra-broadband entangled photon pair bandwidth >5.22 THz. Our approach yields scalable, compact, low-power, and stable sources of polarization-entangled photons, needed for real-world applications of quantum communications and network systems.

Related links:

Read this publication on the npj Quantum Information Website

Return to CQIQC member publications.