Two-photon-pumped frequency-upconverted lasing and optical power limiting properties of vinylbenzothiazole-containing compounds in solution

Two-photon induced frequency-upconversion emission, two-photon-pumped (TPP) lasing and optical limiting properties of trans-2-[p-(N-methyl-N-hydroxyethylamino) styryl]-N-methylbenzothiazolinium iodide ( 1) and trans-2-[p-(N-ethyl-N-hydroxyethylamino) styryl]-N-methylbenzothiazolinium iodide ( 2) were investigated. These two compounds exhibit excellent TPP lasing at 634 nm when pumped with a 1064 nm pulsed laser beam, and highly efficient optical limiting performance in 1 cm path-length dimethyl formamide solution pumped with 1064 nm laser pulses at 0.01 similar to 6.75 mJ. Significantly, these compounds are very stable upon exposure to light for a long time.