Efficient high-energy femtosecond pulse compression in quadratic media with flattop beams.

Using a Gaussian-to-flattop beam reshaper and a frequency-doubling crystal, we demonstrate highly efficient and spatially uniform pulse compression of 1mJ, ~100fs pulses from a regenerative Ti:sapphire amplifier. The technique has general applicability to all-bulk self-defocusing-type cascaded-quadratic compressors, providing a way to increase peak power and intensity for a wide range of amplified femtosecond pulsed lasers.

Spectral shaping to improve the point spread function in optical coherence tomography.

We demonstrate inhibition of the sidelobes of the axial point spread function in optical coherence tomography by shaping the power spectrum of the light source with a remaining power of 4.54 mW. A broadband amplified spontaneous emission source radiating at 1565 +/- 40 nm is employed in a free-space optical coherence tomography system.