Electronically and rapidly tunable fiber-integrable optical parametric oscillator for nonlinear microscopy.

Area of Science:

• Optics and Photonics
• Laser Physics
• Nonlinear Optics

Background:

• Fiber-based optical parametric oscillators (FOPOs) offer compact and robust solutions for generating tunable laser light.
• Traditional FOPOs often require complex setups and precise alignment, limiting their practical applications.

Purpose of the Study:

• To develop a tunable, all-fiber laser source for applications like hyperspectral imaging.
• To demonstrate a FOPO with all-electronic control for simplified operation and alignment-free performance.

Main Methods:

• A fiber-coupled laser diode was used to pump a photonic crystal fiber (PCF) for four-wave mixing (FWM).
• A single-mode fiber (SMF) formed a dispersive resonator to filter the FWM output.
• Dispersion filtering was employed to achieve desired output pulse characteristics.

Main Results:

• Output pulses with a ~3 nm bandwidth, ~8 ps duration, and up to 22 nJ energy were generated.
• Wavelength tuning from 1130 to 1310 nm was achieved within 8 μs by adjusting the pump laser repetition frequency.
• The resonator length remained unchanged during wavelength tuning.

Conclusions:

• The developed FOPO provides tunable, high-energy picosecond pulses in a compact, all-fiber format.
• Its rapid, electronic wavelength tuning and alignment-free operation make it highly suitable for hyperspectral imaging.
• This all-electronic controlled FOPO represents a significant advancement towards a turnkey laser light source.