The effect of BDN-I dye ground-state absorption cross-section in Nd:YAG giant laser pulse power


The Nd:YAG laser system at 1.064 μm has been operated. The BDN-I dye has been prepared and dissolved in many pure polar organic solvent such as ( Carbon-tetra-chloride,Chloroform,Acetone,Dioxane and Pyridine ), and in a mixture of Carbon-tetra-chloride with other solvent at 1:1 , and 2:1 mixing ratios, to act as liquid passive Q-Switch for Nd:YAG laser. The energy and duration of Q-Switching laser pulse has been measured at different molar concentration of the dye dissolved in solvents which mentioned above. The values of ground-state absorption cross-section σ of the saturable absorber (S.A) at different values of dye molar concentration ( M).The effect of ( M) on (σ) , and its relation with giant laser power (P , have been studied .The increasing of (M)causes (P) increasing and (σ) decreasing. The (σ) results have been interpreted according to polarity of used solvent. However the giant laser power results may be explained according to used solvent density. Pyridine solvent is an efficient solvent ,has been concluded because there is no need to higher (M) of dye by using it , and its mixture has high (σ) compared to other solvents . The main conclusion is the mixing way of Carbon-Tetra-Chloride with other solvent at different mixing ratios , is an ideal way for improving the giant laser pulse power higher , and obtaining high (σ) of (S.A).