Solid-state carrier-envelope phase stabilization via quantum interference control of injected photocurrents.

Area of Science:

• Laser Physics
• Quantum Optics
• Semiconductor Physics

Background:

• Mode-locked Ti:sapphire lasers are crucial for ultrafast science.
• Carrier-envelope phase (CEP) stabilization is essential for precision measurements.
• Existing CEP stabilization techniques often require harmonic generation.

Purpose of the Study:

• To demonstrate a novel method for CEP stabilization of mode-locked lasers.
• To utilize quantum interference in semiconductors for phase comparison.
• To eliminate the need for harmonic generation in CEP stabilization.

Main Methods:

• Utilized quantum interference of single- and two-photon absorption pathways in a semiconductor.
• Employed a low-temperature-grown gallium arsenide sample for phase comparison and photocurrent detection.
• Injected photocurrents into a mode-locked Ti:sapphire laser for stabilization.

Main Results:

• Achieved carrier-envelope phase stabilization without harmonic generation.
• Demonstrated phase comparison via photocurrent generated by quantum interference.
• Obtained a carrier-envelope offset beat note fidelity of 30 dB (10-kHz resolution bandwidth).
• Reported out-of-loop phase-noise levels comparable to standard self-referencing techniques.

Conclusions:

• Quantum interference control of injected photocurrents offers an effective CEP stabilization method.
• This technique simplifies laser stabilization by avoiding harmonic generation.
• The results match the performance of established self-referencing methods, indicating high fidelity.