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Fluorescence spectrometer

To record photoluminescence spectra, we use a HORIBA Jobin Yvon Fluorolog-3 model FL3-22 spectrofluorometer. In this spectrometer a HeXe-lamp provides a broad spectrum for excitation. A monochromator is used to select the wavelength of the exciting light, typically between 500nm and 800nm. After the light has interacted with the sample the emission wavelength is selected by a second monochromator. Our spectrometer includes two detectors: a photomultiplier R928P for the detection of visible light and a Symphony InGaAs detector, cooled with liquid nitrogen for detection in the infrared region. The infrared detector can be used in the range of 900nm to 1500nm. We use this spectrometer primarily to carry out photoluminescence measurements of carbon nanotubes with different atomic structures (diameter, chiral angle). In carbon nanotubes the exitonic excitation energies, which are studied by photoluminescence spectroscopy, are largely depending on the nanotube's chiral structure. Photoluminescence maps allow us to analyze each chiral structure's photoluminescence peaks separately.