Breakthroughs in Photon-Number Resolution and Ultra-Fast Detection
Researchers from ID Quantique and the University of Geneva have made a significant advancement in superconducting nanowire single-photon detector (SNSPD) technology. A new 28-pixel parallel SNSPD (P-SNSPD) combines state-of-the-art photon-number resolution (PNR) and ultra-high-speed performance. The published paper is entitled “High photon-number efficiencies with a fast 28-pixel parallel SNSPD.”
Key Highlights
- High detection rate with only a single coaxial read-out line: >50% SDE and 80 ps jitter at detection rates up to 200 Mcps
- State-of-the-art PNR: 75% efficiency for 2-photon events, 60% for 3-photon events, and accurate state reconstruction of Poissonian light at 40 MHz
- Simple, scalable readout: Just a single cryogenic channel per 28-pixel detector, no requirement for high-precision time-tagging, and the ability to discriminate photon numbers in real time without post-processing
P-SNSPD Architecture
Unlike conventional SNSPD arrays that require separate readout channels for each pixel, this design uses a parallel architecture in which all 28 pixels are connected on-chip, with photon-number information encoded in the amplitude of the output pulse. This allows the entire detector to be read out through a single coaxial cable, dramatically simplifying the experimental setup and improving scalability.
Performance at High Speeds
This P-SNSPD shows exceptional high-speed performance, maintaining a system detection efficiency (SDE) of over 50% even at count rates up to 200 MCps, with a timing jitter at that count rate of just 80 ps. Employing just four such detectors, utilizing only four cryogenic read-out channels, the researchers demonstrated a maximum count rate (MCR) of ∼1.3 Gcps. This combination of high-speed performance and minimal readout complexity puts the technology in a strong position for applications requiring extremely high detection rates.
Photon Number Resolution
This parallel architecture allows for determination of photon number states without complex post-processing, simply based on discrimination of the amplitude of its output voltage. The use of many pixels allows scaling of n-photon fidelities close to the ideal “intrinsic” scaling dictated by the device’s single-photon efficiency. This 28-pixel device thus achieves a state-of-the-art 75% efficiency for 2-photon events and 60% for 3-photon events, for example.
The team also successfully reconstructed the statistics of input coherent states at a 40 MHz repetition rate, showcasing the detector’s capabilities for quantum optics experiments.
Implications
The combination of high efficiency and low jitter at high count rates, scalable readout, and state-of-the-art photon number resolution makes many-pixel P-SNSPDs a versatile tool that could have far-reaching impacts on various quantum technologies:
- Quantum network applications, such as faster quantum key distribution systems
- High-speed optical quantum computing protocols
Available Now
This groundbreaking technology is now commercially available as part of ID Quantique’s (IDQ) ID281 or ID281 Pro SNSPD systems. This technology brings cutting-edge photon detection capabilities to researchers and industry professionals worldwide.
To request more information or a quotation for any ID Quantique products, contact IL Photonics.