Balanced photodetector nonlinearity for the short-pulse regime

Area of Science:

• Optics and Photonics
• Semiconductor Devices
• Nonlinear Optics

Background:

• Amplified photodetectors are crucial for high-speed optical measurements.
• Understanding their nonlinear response is essential for accurate signal detection.
• Short-pulse laser characterization provides insights into dynamic behavior.

Purpose of the Study:

• To characterize the nonlinear response of amplified photodetectors using short-pulse lasers.
• To evaluate balanced detectors regarding amplitude, area, broadening, and impulse response mismatch.
• To investigate the dynamic impact of laser pulses on detector performance.

Main Methods:

• Utilized short-pulse lasers to probe amplified photodetector behavior.
• Performed detailed characterization of two balanced detector models.
• Analyzed parameters including amplitude, area, broadening, and impulse response mismatch.

Main Results:

• Demonstrated that short laser pulses induce nonlinearities in photodetectors.
• Observed nonlinear effects even when average power is below the continuous saturation threshold.
• Quantified detector response characteristics like amplitude, area, and impulse response mismatch.

Conclusions:

• Short-pulse laser illumination triggers significant nonlinearities in amplified photodetectors.
• Nonlinearities can be present at average power levels not typically considered saturating.
• Accurate characterization of impulse response mismatch is vital for balanced detector applications.