Improved temporal stability of polymethine laser dyes in aqueous solutions

Polymethine laser dyes which fluoresce in the near infrared in organic solvents generally exhibit poor temporal stability at room temperature. Two typical laser-pumped polymethine dyes in aqueous solutions containing nonionic surfactants are investigated. Temporal stability was improved 20-fold, as compared to organic solutions, with no significant changes in laser-pumping threshold or tuning range.