Organic multilayers as distributed Bragg reflectors

We report on a distributed Bragg reflector (DBR) operating in the IR spectr al region, based on a fluorocarbon polymer (CFx) multilayer. In this organi c structure, the periodic variation of the refractive index is obtained by embedding gold clusters in the CFx, resulting in a periodic CFx/CFx(Au) lay ered structure with a refractive index discontinuity in the infrared spectr al region of about Delta n similar to 0.4. We have fabricated a quarter-wav elength stack consisting of 4 CFx/CFx(Au) pairs, with a nominal Au concentr ation equal to 17%. The DBR shows a reflectance peak of about 70% at 1.7 mu m and a full width at half maximum of about 0.4 mu m. (C) 1999 American In stitute of Physics. [S0003-6951(99)04129-7].