Single-/dual-pulse repetition rate variable supercontinuum light source with peak wavelength around 1.7  µm using a...

Area of Science:

• Nonlinear Optics
• Fiber Optics
• Laser Technology

Background:

• Supercontinuum generation is crucial for various optical applications.
• Controlling pulse characteristics in supercontinuum sources remains a key research area.

Purpose of the Study:

• To propose and experimentally demonstrate a variable repetition rate supercontinuum light source (SLS) around 1.7 µm.
• To enable switching between single-pulse and dual-pulse operation for diverse applications.

Main Methods:

• Utilized a 1.5 µm modulated pump source with a laser and intensity modulator (IM).
• Employed a 1 km high nonlinear fiber (HNLF) as the nonlinear gain medium.
• Incorporated a Sagnac loop to achieve multiwavelength pulse generation and filtering of residual pump using a wavelength division multiplexer.

Main Results:

• Achieved a supercontinuum spectrum spanning 1.59 to 1.96 µm with a peak wavelength around 1.7 µm.
• Demonstrated tunable single/dual-pulse generation by adjusting IM parameters.
• Obtained dual-pulse durations from 60 ps to 180 ps with a 40% duty cycle at repetition rates from 170 MHz to 2 GHz.

Conclusions:

• The developed single-pulse SLS around 1.7 µm can enhance optical coherence tomography (OCT) performance.
• The dual-pulse SLS serves as a valuable reference for laser drilling applications.