STUDY ON LIGHT LOCALIZATION OF ONE-DIMENSIONAL DISORDERED MULTILAYER

Antimonite and cryolite are used as the high and low refractive index coating materials to be evaporated alternately to the glass substrates . All cryolite layers have the same thickness d/4n(a), and the thickne ss of antimonite layers varies randomly around an average value d/4n(b ), with d=650 nm, n(a) and n(b) their refractive indices. Three kinds of multilayer are prepared, they possess the same degree of thickness disorder, but different total lengths, i.e., 10, 15 and 21 periods. We measure the transmission and reflection spectrum after the light pass ing through these multilayers. The exponential intensity variation ver sus total length is experimentally demonstrated, and the light localiz ation length is then obtained. Our experimental results can be fitted very well with the numerical simulation. Based on the measured and cal culated localization length, the effects of phase coherent Bragg refle ction and Anderson localization are discussed.