Electronically delay-tuned upconversion cross-correlator for characterization of mid-infrared pulses

Area of Science:

• Optics and Photonics
• Laser Spectroscopy
• Ultrafast Optics

Background:

• Characterizing mid-infrared (mid-IR) pulses is crucial for various scientific applications.
• Traditional methods often rely on mechanical delay tuning, which can be slow and complex.
• Developing faster, more precise characterization techniques is an ongoing challenge in ultrafast optics.

Purpose of the Study:

• To present a novel method for time-resolved spectral characterization of mid-infrared pulses.
• To demonstrate the efficacy of electronic delay tuning as an alternative to mechanical delay tuning.
• To enable rapid acquisition of full wavelength/time spectrograms for ultrafast pulses.

Main Methods:

• Development of a cross-correlator system with no moving parts.
• Integration of ultra-broadband pulsed upconversion detection.
• Implementation of fast active electronic delay tuning for precise temporal control.
• Acquisition of spectrograms over a wide temporal range with high resolution.

Main Results:

• Successful time-resolved spectral characterization of 1.6 ns mid-infrared supercontinuum pulses.
• Demonstration of electronic delay tuning enabling spectrogram acquisition in seconds.
• Achieved 48 ps temporal resolution and 22 cm^-1 spectral resolution in the 2700-4300 nm range.
• Potential for delay ranges extending to microseconds.

Conclusions:

• Electronic delay tuning is a viable and advantageous alternative to mechanical delay tuning.
• The developed method offers significant improvements in speed and precision for pulse characterization.
• This technique has strong potential for applications in cross-correlators and laser spectroscopy.
• The system's fast tunability and long delay ranges are key assets for advanced optical measurements.