A two-color dual-comb system for time-resolved measurements of ultrafast magnetization dynamics using triggerless...

Area of Science:

• Physics
• Materials Science
• Optics

Background:

• Ultrafast demagnetization and spin dynamics in magnetic materials are crucial for advanced technologies.
• Current pump-probe techniques often require precise triggering, limiting measurement speed and complexity.

Purpose of the Study:

• To develop a triggerless asynchronous optical sampling system for studying ultrafast spin dynamics.
• To characterize demagnetization and spin precession in magnetic thin films with high temporal resolution.

Main Methods:

• Utilized an Er-doped fiber (EDF)-laser-based dual-comb system for pump-probe spectroscopy.
• Employed highly nonlinear fiber broadening and Yb-doped fiber amplification for one comb, and second harmonic generation for the other.
• Achieved stabilized frequency comb oscillations to suppress timing jitter for triggerless data acquisition.

Main Results:

• Successfully observed ultrafast demagnetization and spin precession dynamics in permalloy thin films.
• Demonstrated picosecond and nanosecond time-scale resolution of spin dynamics.
• Validated the capability of triggerless asynchronous optical sampling for pump-probe measurements.

Conclusions:

• The developed EDF-laser dual-comb system enables efficient, triggerless investigation of ultrafast spin phenomena.
• This time-domain spectroscopy approach shows significant promise for rapid characterization of spin-wave dynamics.
• The system offers a new pathway for exploring fundamental magnetic material properties.