Spectroscopy and Laser Applications

Molecular spectroscopy uses the way matter absorbs and emits light to identify and quantify substances with extraordinary precision, and pairing that principle with modern laser sources has transformed what is measurable, down to trace gases at parts-per-trillion concentrations. Infrared and terahertz lasers—including quantum-cascade devices and frequency combs—now enable real-time detection of combustion intermediates, atmospheric pollutants, and disease markers in exhaled breath, while curated molecular databases like HITRAN and HITEMP provide the reference line parameters that make quantitative identification possible. A central challenge is extending accurate spectroscopic databases to the high temperatures relevant to engines and planetary atmospheres, where molecules occupy excited states whose transitions are poorly catalogued. Researchers are also pushing laser-based techniques such as photoacoustic and cavity ring-down spectroscopy toward greater sensitivity, miniaturization, and speed, aiming to move precision measurements out of the laboratory and into industrial and medical settings.

Works

109,403

Total citations

1,458,390

Keywords

Spectroscopic DatabasesTerahertz Quantum-Cascade LasersInfrared Laser AbsorptionGas SensingPhotoacoustic SpectroscopyHigh-Temperature Molecular Spectroscopy