Improved Laser‐Based Photoluminescence on Single‐Walled Carbon Nanotubes

Photoluminescence (PL) is a common tool to characterize various properties of single-walled carbon nanotube (SWCNT) chirality distribution and the level of tube individualization in SWCNT samples. Most PL studies use conventional lamp light sources whose spectral distribution is filtered with a monochromator, but this results in a still impure spectrum with a low spectral intensity. Tunable dye lasers offer a tunable light source which cover the desired excitation wavelength range with a high spectral intensity, but their operation is often cumbersome. Herein, the design and properties of an improved dye-laser system which is based on a Q-switch pump laser are presented. The high peak power of the pump provides an essentially threshold-free lasing of the dye laser, which substantially improves the operability. It allows operation with laser dyes, such as Rhodamin 110 and Pyridin 1, which are otherwise on the border of operation of the laser. The system allows to cover the 540-730 nm wavelength range with four dyes. In addition, the dye laser output pulses closely follow the properties of the pump, which directly provides a time-resolved and tunable laser source. The performance of the system by measuring the PL map of a HiPco SWCNTs sample is demonstrated.