Superradiant dye solution laser with two-photon picosecond optical pumping

Multiphoton Absorbing Materials: Molecular Designs, Characterizations, and Applications

“…In practice, the earliest two-photon pumped (2PP) lasing was observed during the 1960s−1970s in several semiconductor crystals operating at low temperature. − Also, there were a few papers reporting two-photon excited stimulated emission in gas and metal vapor systems during the 1970s−1990s. − On the other hand, between the 1970s and 1993, there were several experimental reports on two-photon excited stimulated emission for commercial organic dye systems. − In these cases with no cavity enhancement, most of the observed output was the so-called amplified spontaneous emission (ASE) that usually was only characterized by spectral narrowing, not by high directionality. In 1995, He et al reported 2PP cavity lasing with a narrow spectral line width and high directionality for solutions of a novel dye and for doped solid matrixes …”

“…[385][386][387][388][389][390] On the other hand, between the 1970s and 1993, there were several experimental reports on two-photon excited stimulated emission for commercial organic dye systems. [391][392][393][394][395][396][397][398] In these cases with no cavity enhancement, most of the observed output was the so-called amplified spontaneous emission (ASE) that usually was only characterized by spectral narrowing, not by high directionality. In 1995, He et al reported 2PP cavity lasing with a narrow spectral line width and high directionality for solutions of a novel dye and for doped solid matrixes.…”

Nonlinear multiphoton processes in organic and polymeric materials

“…By contrast, two-photon pumped lasing in organic dyes involves a direct absorption of two photons through virtual states. Since its first observation in 1971, several papers have been published about upconverted stimulated emission in solutions of commercial dyes such as Rhodamine 6G, Rhodamine B, and PYC [31][32][33][34][35][36][37]. However, most of these papers report observation of amplified spontaneous emission (ASE) as opposed to cavity lasing.…”