Nonlinear optical effects in nano-sized ferroelectrics Sr6Ti2Nb(Ta)8O30

Abstract: Enhancement of the second-harmonic generation (SHG) efficiency has been observed in nanocrystallites of ferroelectric Sr6Ti2Nb8O30 and Sr6Ti2Ta8O30. The enhancement was observed in particle sizes below 150 nm. The particles were incorporated, with an applied electric field, into a photopolymer polyvinyl alcohol matrix. The maximum SHG output was achieved with a nanocrystallite content of about 4.2%, with respect to mass. An increase of the second-order optical susceptibility, to about 3.2 pm/V and 2.4 pm/V for Sr6Ti2Nb8O30 and Sr6Ti2Ta8O30 respectively, was observed with a decrease in particle size from 250 nm to 70 nm. [Copyright &y& Elsevier]