ABSTRACT
Photoluminescence properties of semiconducting single-wall carbon-nanotube (s-SWNT) thin films with different metallic single-wall carbon-nanotube (m-SWNT) concentrations are reported. s-SWNT purified samples are obtained by polymer-assisted selective extraction. We show that the presence of a few m-SWNTs in the sample generates a drastic quenching of the emission. Therefore, the highly purified s-SWNT film is a strongly luminescent material and a good candidate for future applications in photonics, such as near-IR emitters, modulators, and detectors.
ABSTRACT
We demonstrate passive mode locking of solid-state lasers by saturable absorbers based on carbon nanotubes (CNT). These novel absorbers are fabricated by spin-coating a polymer doped with CNTs onto commercial dielectric laser-mirrors. We obtain broadband artificial saturable absorber mirrors with ultrafast recovery times without the use of epitaxial growth techniques and the well-established spin-coating process allows the fabrication of devices based on a large variety of substrate materials. First results on passive mode locking of Nd:glass and Er/Yb:glass lasers are discussed. In the case of Er/Yb:glass we report the to our knowledge shortest pulse generated in a self-starting configuration based on Er/Yb:bulk-glass: 68 fs (45 fs Fourier-limit) at 1570 nm wavelength at a pulse-repetition rate of 85 MHz.