Silicon Quantum photonics
Developing components for quantum communications and computing
Quantum photonics is key to ensure ultra-safe data transmission. It also has recently emerged as a potential path towards quantum computing.
Ensuring large-scale integration is necessary to enable quantum applications. To achieve massive integration, CEA-Leti leverages its mature Si and SiN photonics platform for the development of low-loss quantum photonic hardware.
CEA-Leti specifically develops quantum-grade photonic integrated components & circuits for the generation, fast encoding, coherent manipulation & detection of photonic qubits. CEA-Leti components are compatible with discrete or continuous variable approaches.
The goal?
CEA-Leti aims at contributing to the future generation of miniaturized ultrasecure quantum communication systems, either fiber-based or in free-space, by developing integrated quantum transmitter and receiver circuits matching the specifications of the most advanced quantum communication protocols, such as device-independent ones.
CEA-Leti also aims at contributing to the development of integrated quantum photonic processors relying for example on measurement-based quantum computing protocols. We address the heart of the programmable quantum processor while ensuring seamless generation of entangled photon cluster states and their high-efficiency detection on-chip.
What does it require?
CEA-Leti’s experts are developing key integrated components and circuits to enable advanced quantum key distribution protocols and quantum processing:
Single photon generation
- Hybrid III-V/Si lasers delivering weak coherent pulses [1]
- High-Q ring resonators delivering heralded single photons (currently MHz rate, targeting GHz rate)[2]
Photon fast encoding and coherent manipulation
- Loss-free thermo-optic phase shifters
- Fast phase shifters based on free-carrier plasma dispersion
- Towards fast & low-loss Pockels phase shifters
Single photon detection
- HgCdTe avalanche photodiodes[3] with a world-record speed for the detection of mesoscopic photon states
- Optimized NbN material[4] for superconducting nanowire single photon detectors with high efficiency and low dark counts
Publications
1. C. Agnesi et al., Hong-Ou-Mandel interference between independent III-V on silicon waveguide integrated lasers, Opt. Exp. 44, 271 (2019)
2. H. El Dirani et al., Low-loss silicon technology for high-Q bright quantum source, proc. of IEEE Group IV Photonics Conference (2019)
3. J. Rothman et al., Meso-photonic detection with HgCdTe APDs at highcount rates, J. of Electron. Mat., https:// doi.org/10.1007/s11664-020-08461-8, 2020
4. R. Rhazi et al., Improvement of critical temperature of niobium nitride deposited on 8-inch silicon wafers thanks to an AlN buffer layer, Superconduct. Sc. and Technol. 34, 045002 (2021) |