Temporal and spatial multiplexed infrared single-photon counter based on high-speed avalanche photodiode

Area of Science:

• Quantum optics
• Photon detection

Background:

• Single-photon counters are crucial for quantum information processing.
• Existing detectors face limitations in speed and photon-number resolution.

Purpose of the Study:

• To develop and characterize a high-speed temporal and spatial multiplexed single-photon counter.
• To assess its photon-number-resolving capability up to four photons.

Main Methods:

• Utilized a fiber loop for optical pulse manipulation.
• Employed a 200 MHz dual-channel single-photon detector based on InGaAs/InP avalanche photodiodes.
• Performed quantum detector tomography to reconstruct the positive-operator-valued measure and Wigner functions.

Main Results:

• Demonstrated a single-photon counter with photon-number resolution up to four photons.
• Characterized detector performance despite afterpulsing noise and limited detection efficiency.

Conclusions:

• The developed temporal and spatial multiplexed single-photon counter is suitable for quantum information schemes.
• The detector's high speed and photon-number resolution open possibilities for advanced quantum applications.