An organic-inorganic crystal for blue SHG: crystal growth and quadratic optical effect of 2-amino-5-nitropyridinium chloride

The effective quadratic coefficients 2-amino-5-nitropyridinium chloride (2A 5NPCl) are measured by phase matched second harmonic generation. 2A5NPCl is an interesting material for quadratic nonlinear optics due to the quasi-op timized arrangement of 2A5NP units in herringbone motifs and the high densi ty of nonlinear 2-amino-5-nitropyridinium chromophore per unit volume. The maximum effective coefficient is obtained as 9.7 pm/V at 1320 nm. Since 2A5 NPCl crystal is transparent from 410 to 1650 nm, sum frequency generation i s also carried out with incident beams of 1320 and 660 nm. In this study, 1 1% conversion efficiency from 660 to 440 nm is obtained for 1.6 mm interact ion length. (C) 1999 Elsevier Science B.V. All rights reserved.