Multicolor second harmonic generation by strontium barium niobate nanoparticles

Infrared to visible second harmonic generation (SHG) has been demonstrated from 40 nm Sr(0.6)Ba(0.4)Nb(2)O(6) nanoparticles in a broad spectral range of infrared fundamental wave excitation (800-1200 nm). The efficiency for SHG is compared with that obtained from powdered samples of larger crystallite sizes so that the mechanism leading to optical frequency conversion is discussed. The obtained results point out the possibility of using nonlinear nanoparticles for multifrequency optical imagin