Spectroscopy

Our lab has a variety of spectrophotometers and spectroscopy apparatuses.

Transmission and Absorbance
Our lab has several spectrophotometers capable of measuring the transmission of light through materials, which can be converted to absorbance using Beer's Law. These spectrometers include a UV-Vis-NIR Jasco V-670 spectrophtomer and StellarNet miniature spectrometers.

Fluorescence
Several spectrometers are available for fluorescence characterization. A Perkin Elmer LS45 Luminescence spectrometer allows for excitation and emission scans of both solution and films, while several Ocean Optics spectrometers, coupled with a LabSphere integrating sphere and monochromatic light source allow for relative quantum yield calculation and fluorescence spectra.

Photothermal Deflection Spectroscopy
When transmittance via a spectrophotometer is not of high enough resolution, we boast a photothermal deflection spectroscopy (PDS) system to accurately measure the absorption coefficient of materials. To measure the non-radiative optical absorption of a sample, a position sensitive sensor measures the bending of a probe laser beam in a solution that has a highly fluctuating index of refraction with change in temperature. Samples are placed into this solution and heated by monochromatic light, thus bending the laser as they heat the surrounding solution. PDS allows for highly accurate absorption measurements, showing absorption due to trap states in semi-conductors and slight fluctuations in absorption due to changes in a material.

Mass Spectroscopy
Our lab possesses a SRS Residual Gas Analyzer, allowing for detailed gas analysis for vacuum systems up to 200 amu. The system includes a real-time Windows software package for data acquisition and analysis.