Integrated autocorrelator based on superconducting nanowires.

Area of Science:

• Quantum Optics
• Integrated Photonics
• Superconducting Nanowire Single-Photon Detectors

Background:

• Accurate measurement of photon statistics is crucial for quantum information processing and optical metrology.
• On-chip integration of quantum optical components offers miniaturization and enhanced functionality.
• Superconducting single-photon detectors (SSPDs) provide high efficiency and fast response times for photon detection.

Purpose of the Study:

• To demonstrate an integrated autocorrelator for on-chip measurement of the second-order intensity correlation function, g(2)(τ).
• To evaluate the performance of the integrated device in terms of quantum efficiency and timing jitter.

Main Methods:

• Fabrication of an integrated autocorrelator device using two superconducting single-photon detectors patterned on a GaAs ridge waveguide.
• Characterization of the device's polarization-independent quantum efficiency and timing jitter at 1300 nm.
• Measurement of g(2)(τ) for both continuous-wave and pulsed laser excitations.

Main Results:

• Demonstration of an on-chip autocorrelator enabling g(2)(τ) measurements.
• Achieved a polarization-independent device quantum efficiency in the 1% range.
• Reported a timing jitter of 88 ps at 1300 nm.
• Successfully performed g(2)(τ) measurements for continuous-wave and pulsed lasers with no measurable crosstalk.

Conclusions:

• The integrated autocorrelator based on SSPDs on a GaAs waveguide is a viable platform for on-chip photon statistics measurements.
• The device exhibits promising performance metrics, including polarization independence and low timing jitter.
• This technology has potential applications in quantum communication, quantum computing, and fundamental quantum optics research.