Complex electro-optic constants of dye-doped polymer films determined with a Mach-Zehnder interferometer

Abstract

The real and imaginary parts of the linear electro-optic (EO) constants of four dyes, i.e., N,N-dimethylaminonitrostilbene (DANS), 4-[N-(2-hydroxyethyl)-N- ethyl]amino-4'-nitroazo- benzene [disperse red 1 (DR1)], N,N-dimentylindoaniline [phenol blue (PB)], and 1,1',3,3,3',3'-hexamethylindotricarbocyanine iodide (HITCI) in polymethylmethacrylate (PMMA) films were determined using a Mach-Zehnder interferometer. The electronic transitions of DANS, DR1, PB, and HITCI are off-resonant, near-resonant, and resonant on the higher and lower energy sides with a He-Ne laser wavelength (632.8 nm), respectively. The different ratios of the real and imaginary parts of the EO constants of four dyes including their signs are successfully explained in terms of detuning energy. © 1995 American Institute of Physics.