We propose a new approach for generating broadly tunable and energetic femtosecond pulses using a dispersion-managed planar-concave multi-pass cell. By optimization of the intracavity dispersion, 4.5- \(\upmu\) J, 65-fs input pulses centered at 1030 nm were spectrally broadened by self-phase modulation to a 20-dB bandwidth exceeding 300 nm. The broadened spectrum consists of well isolated spectral lobes. Selection of the leftmost spectral lobe using a proper optical filter produces 0.76- \(\upmu\) J, 78-fs pulses at 920 nm, and selection of the rightmost spectral lobe corresponds to 0.83- \(\upmu\) J, 108-fs pulses at 1160 nm. Wavelength tuning can be realized by varying the input pulse energy. With excellent energy scalability, this new approach offers a simple and reliable solution for applications (e.g., multiphoton microscopy) requiring energetic femtosecond pulses at wavelengths that cannot be directly provided by mode-locked lasers.
