By Istituto Italiano di Tecnologia
By combining optical, vibrational and electronic spectroscopy, we investigate the optoelectronic properties of semiconductors, how they are affected when forming interfaces. Our labs feature a variety of light sources and flexible setups for the study of the photophysical properties of semiconductors: TRPL Lab is dedicated to time-resolved photoluminescence. A tunable ultrafast oscillator (Chameleon, 80 MHz) coupled to an optical parametric oscillator provides excitation from the NIR (950 nm) to UV (350 nm). The resulting photoluminescence can be measured with a time resolution of 1.6 ps in the visible range (Hamamatsu Streak Camera, up to 900 nm), and 1 ns in the IR (TCSPC, up to 1400 nm). CW Lab offers a variety of light sources on CW or low repetition rate mode. These can be coupled with flexible photoluminescence lines and integrating spheres to test our materials under varied illumination conditions or used in connection with a spectrophotometer (200-2500 nm) and a spectrofluorometer (300 nm-1700 nm).Particularly useful for perovskite research is our Photothermal Deflection Spectroscopy (PDS) set-up, to probe weak sub-bandgap absorption up to five orders of magnitude below that at the band-edge. Femtosecond Lab. This lab hosts a femtosecond laser system dedicated to ultrafast time-resolved spectroscopies, including a transient absorption spectrometer, excitation correlation photoluminescence (ECPL) and optical gain measurements. This laser system is coupled with our Photo-Emission Electron Microscope (tr-PEEM). One novelty of our time-resolved systems is the particularly large range of accessible time delays, over 10 orders of magnitude (10-13–10-3 s). The spectroscopy equipment also includes a high magnification fluorescence microscope equipped with a hyperspectral camera, which allows to measure spectral-resolved fluorescence images with 1 micrometer of spatial resolution and 400-1000 nm wavelength range. Our optical labs are equipped with vacuum and cryogenic equipment which allows us to perform experiments in a controlled atmosphere and down to 4 K.
