Optical properties of quantum-dot-decorated polymer nanofibers

We report a one-step process for decorating poly(trimethylene terephthalate) (PTT) nanofibers with CdSe/ZnS core/shell quantum dots (QDs). Using the QD-decorated PTT nanofibers with diameters of 400-800 nm as active subwavelength waveguides, their high photostability for 630 nm red light and low absorption coefficient down to 2.6 cm(-1) were characterized by both evanescent waveguiding excitation and irradiation excitation. Compared with the irradiation excitation, a 200 times enhancement was obtained from the active subwavelength waveguides under the evanescent waveguiding excitation.