Dynamic properties and optical phase conjugation of two-photon pumped ultrashort blue stimulated emission in a chromophore solution

Abstract

The dynamic properties of two-photon pumped blue lasing $(\ensuremath{\sim}470\phantom{\rule{0.3em}{0ex}}\mathrm{nm})$ in the solution of an organic chromophore [2-acetyl-6-(dimethylamino)naphthalene], excited by $\ensuremath{\sim}160\text{\ensuremath{-}}\mathrm{fs}$ laser pulses at $\ensuremath{\sim}775\phantom{\rule{0.3em}{0ex}}\mathrm{nm}$, have been studied. Both the forward and backward stimulated emission are enhanced by feedback from the reflection at the two optical windows of the solution filled cuvette. Under current experimental conditions, the lasing wavelengths in the forward and backward directions were almost the same, but both blueshifted compared to the fluorescence peak wavelength of the sample solution. The temporal behavior of the lasing output was recorded by a high-speed streak camera system. The multipulse structure and spectral properties of the output lasing are semiquantitatively explained. In addition, excellent optical phase-conjugation properties of the backward stimulated emission were observed; the aberration influences from an aberrator on the backward lasing beam were automatically removed.