Single-cycle mid-infrared pulses with 30 μJ at 100 kHz via post-compression in solid-state media

Area of Science:

• Laser physics
• Mid-infrared optics
• Ultrafast science

Background:

• Optical Parametric Chirped Pulse Amplification (OPCPA) is a powerful technique for generating high-energy ultrashort laser pulses.
• Achieving single-cycle pulses in the mid-infrared (MIR) region with high energy and stability is crucial for advanced applications.
• Post-compression techniques are essential for further reducing pulse durations from OPCPA systems.

Purpose of the Study:

• To demonstrate a novel two-stage bulk post-compression technique for OPCPA systems.
• To achieve single-cycle pulse generation in the mid-infrared at high pulse energy.
• To evaluate the stability and uniformity of the generated ultrashort pulses for scientific applications.

Main Methods:

• Utilized a 10 W four-cycle OPCPA system as the initial source.
• Employed a two-stage bulk post-compression method using barium fluoride (BaF2) and silicon (Si) crystals.
• Optimized the tandem crystal configuration to achieve pulse compression and maintain carrier-envelope phase (CEP) stability.
• Investigated high-order harmonic generation in ZnO with locked CEP.

Main Results:

• Generated 3.2 µm mid-infrared pulses with 30 µJ energy and a compressed pulse duration of 11 fs.
• Achieved a carrier-envelope phase (CEP) stability of 145 mrad RMS.
• Observed high spatio-spectral uniformity with minimal spatial and angular chirp.
• Demonstrated reliable and long-term stable system performance.
• Successfully generated high-order harmonics in ZnO with locked CEP.

Conclusions:

• The developed two-stage bulk post-compression technique effectively generates high-energy, single-cycle mid-infrared pulses.
• The system's high performance, including CEP stability and spatio-spectral uniformity, makes it suitable for demanding ultrafast and attosecond science experiments.
• The demonstrated reliability and stability pave the way for advanced research in strong-field physics and attosecond science applications.