Quantum-Optic Silicon as a Commodity: Extending the Trust Continuum till the Edge of ICT Networks

The rapid rise of quantum computation has raised concerns about conventional encryption methods.

In response to this emerging threat, quantum key distribution (QKD) offers an information-theoretically secure key exchange.

However, its complexity currently hinders its widespread adoption.QOSiLICIOUS introduces a disruptive “commodity” approach, integrating every element of quantum random number generation (QRNG) and QKD monolithically on silicon.

This results in ultra-compact implementations with clear photonic/microelectronic co-integration strategy and excellent cost credentials allowing us to address new QKD markets.

A pixel-size (0.01 mm²) QRNG will be realized in 0.18-µm CMOS, including a multi-dot silicon light emitting diode surrounded by a ring-shaped single-photon avalanche detector (SPAD) with co-integrated active quenching.

Its true random numbers will feed a QKD transmitter developed on a silicon-photonic BiCMOS platform on a footprint of no more than 1 mm². Simplicity is ensured through a novel GeSi light emitter sourcing a BB84 polarization state encoder. This yields an all-silicon solution free from the burden of complex and costly III-V / silicon hetero-integration.

The efforts on QOSiLICIOUS’ QKD transmitter are complemented by surface-normal GeSi SPAD technology for 1550-nm operation at detection efficiencies of 50% under Peltier cooling.

The GeSi SPAD will be transferred to the waveguide-based silicon-photonic platform to further yield an integrated QKD receiver including BB84 state analysis.The applicability of QOSiLICIOUS’ technology to commodity segments will be evaluated in techno-economic challenging scenarios (i) intra-datacenter interconnects, (ii) access and 6G networks and (iii) mobile applications with a close-proximity free-space optical key exchange.

Performance evaluation activities will target secure-key generation that enables the encryption of co-existing classical data traffic through fast AES key renewal.