Fingerprinting molecules based on direct measurement of absorption spectrum by frequency-tuning monochromatic THz source

We have demonstrated that by directly measuring the absorption spectrum of the chemicals in the vapor phase, we are able to fingerprint molecules. This process is made possible by frequency-tuning a widely-tunable THz source developed by us recently. In the THz region, we can use a set of the absorption peaks due to rotational transitions to truly fingerprint chemical species.