SNSPD-based detector system for NASA's Deep Space Optical Communications project.

Area of Science:

• Quantum optics
• Detector technology
• Optical communications

Background:

• Superconducting nanowire single-photon detectors (SNSPDs) are crucial for sensitive optical measurements.
• NASA's Deep Space Optical Communications (DSOC) project requires advanced detectors for deep space communication.

Purpose of the Study:

• To develop and characterize a free-space-coupled superconducting nanowire single-photon detector array for NASA's DSOC project.
• To serve as the primary downlink detector for the DSOC ground receiver at the Hale Telescope.

Main Methods:

• A 64-pixel WSi SNSPD array was fabricated with four quadrants of 16 co-wound pixels.
• The array was integrated into a cryogenic optical system for filtering and focusing.
• Detector performance was evaluated for system detection efficiency, false count rate, timing jitter, and count rate.

Main Results:

• Achieved a peak system detection efficiency of 76% at 1550 nm.
• Demonstrated a low background-limited false count rate of 3.7 kcps across the array.
• Exhibited timing jitter below 120 ps FWHM and a maximum count rate of approximately 1 Gcps.

Conclusions:

• The developed SNSPD array meets the demanding requirements for deep space optical communications.
• This detector technology is vital for enabling high-bandwidth communication over vast interplanetary distances.
• The successful implementation at the Hale Telescope paves the way for future optical communication missions.