Shaper-assisted phase optimization of a broad "holey" spectrum

Area of Science:

• Nonlinear Optics
• Quantum Optics
• Spectroscopy

Background:

• Broadband optical spectra are crucial for synthesizing arbitrary optical waveforms.
• Controlling the phase of multiple spectral components is challenging.
• Coherent Raman sidebands offer a promising route to generating structured spectra.

Purpose of the Study:

• To develop and demonstrate a technique for optimizing the phase of spectrally-separated frequency sidebands.
• To overcome limitations in temporal shaping for broadband spectra.
• To explore the impact of phase optimization on nonlinear frequency generation.

Main Methods:

• Generating multiple-order coherent Raman sidebands using femtosecond pump and Stokes beams in synthetic single-crystal diamond.
• Combining sidebands into a single beam and analyzing phase coherence through interference measurements.
• Utilizing an acousto-optic pulse shaper to vary individual sideband phases.
• Investigating second harmonic/sum frequency generation as a function of phase variations.

Main Results:

• Demonstrated phase coherence among multiple Raman sidebands.
• Successfully optimized the phase of a broad "holey" spectrum, overcoming pulse shaper limitations.
• Showcased the influence of individual sideband phases on nonlinear frequency conversion processes.

Conclusions:

• The developed step-by-step phase optimization technique is effective for "holey" spectra.
• This method can be extended to synthesize arbitrary optical waveforms from structured sidebands.
• The findings have implications for advanced optical waveform generation and nonlinear optics applications.