Role of host liquid in optical limiting in ink suspensions

Optical limiting of 532 nm, 15 ns duration laser pulses in suspensions made by diluting black ink in water, ethanol, and isopropanol was studied and the strength of limiting was found to be quite different for the three suspensions. Microscopic investigations showed that the sizes of suspended aggregates were different for different host liquids. The suspension with largest aggregate was found to exhibit strongest optical limiting. Our work thus shows that host liquid influences optical limiting in suspensions not only through its thermodynamic properties but also by determining the particle size which has a strong effect on limiting strength.