Long aliphatic chain coated rare-earth nanocrystal as polymer-based optical waveguide amplifiers

Oleic acid-coated erbium-ytterbium co-doped NaYF(4) nanocrystals, NaY(78%)F(4) : Yb(20%)Er(2%), have been synthesized. The cubic nanocrystals were of an average size of 10 nm. The nanocrystals showed excellent redispersibility in common organic solvents and the KMBR (R) polymer matrix. An optical waveguide amplifier was fabricated by doping 0.1 wt% of the nanocrytals into the KMPR (R) polymeric host. At a small input signal power of 150 nW and a pump power of 150 mW, an optical gain of 4.81 dB cm(-1) at 1535 nm was achieved.