We have synthesized stoichiometric batches of GaSe by reacting mixtures of
the parent components and have grown centimeter-size modified single crysta
ls of GaSe by the vertical Bridgman technique. GaSe crystals doped with sil
ver, indium and silver gallium selenide were fabricated for wavelength conv
ersion. Silver doping produced scattering centers which could be dissolved
by annealing at temperatures above 700 degrees C. Crystals cracked extensiv
ely during the annealing process and optical quality deteriorated. SHG meas
urements of In-doped crystals showed a "d" value of 49 pm/V for low concent
ration In-doped GaSe crystals. The silver gallium selenide doped GaSe cryst
als showed a "d" value of 75 pm/V which resulted in significant increase in
the "d(2)/n(3)". (C) 1999 Published by Elsevier Science B.V. All rights re
served.