The recipient of a PhD in physics from Wesleyan University, Andrew Kortyna is a research associate at Joint Institute of Laboratory Astrophysics. Andrew Kortyna is experienced with the use of laser technology, and is a co-author of several scientific publications including "Pulse Propagation Effects in Optical 2D Fourier-Transform Spectroscopy: Experiment."
An analytic technique, Fourier transform infrared (FTIR) spectroscopy makes use of the infrared spectrum of electromagnetic waves to determine the molecular composition of substances. During FTIR spectroscopy, infrared (IR) light is emitted from a source such as a laser, and passes through an interferometer, which modulates and records frequency of the light. When the sample of interest is exposed to this IR light, either the transmitted or scattered rays are recorded by a detector. The time varying signal from the detector is known as an interferogram. The relationship between time and frequency, known as a Fourier transform, is used to displayed an intensity versus frequency plot, called a spectrum.
FTIR spectroscopy is based on the principle of the behavior of molecular vibrations when exposed to external energy (IR light in this case). When a molecule absorbs external energy, it becomes excited from a lower vibrational energy level to a higher vibrational energy level, which has an energy difference that is equal to the energy (i.e., frequency) of the absorbed light. The absorbed frequency patterns vary among different chemicals, with any given chemical exhibiting a characteristic "fingerprint" absorption pattern which is different than the absorption pattern from any other chemical. These absorption patterns can be used like human fingerprints to identify individual chemicals in an unknown sample.
