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Laser Spectroscopy

  1. Massimo Inguscio1,
  2. Giulia Rusciano2,
  3. Antonio Sasso3

Published Online: 15 MAR 2011

DOI: 10.1002/3527600434.eap706

Encyclopedia of Applied Physics

Encyclopedia of Applied Physics

How to Cite

Inguscio, M., Rusciano, G. and Sasso, A. 2011. Laser Spectroscopy. Encyclopedia of Applied Physics. 463–508.

Author Information

  1. 1

    Universita di Firenze, LENS-European Laboratory for Non-Linear Spectroscopy and Dipartimento di Fisica, Sesto Fiorentino-Firenze, Italy

  2. 2

    Universitá di Napoli “Federico II”, Dipartimento di Scienze Fisiche, Napoli, Italy

  3. 3

    Universitá di Napoli “Federico II”, Dipartimento di Scienze Fisiche, Napoli, Italy

Publication History

  1. Published Online: 15 MAR 2011


Most of the actual knowledge of atomic and molecular structure derives from spectroscopic analysis of the radiation emitted when atoms or molecules are properly excited. The foundation of spectral analysis dates back to about 1860, with the work of Kirchhoff and Bunsen which argued that from the analysis of the emission by sample after a proper excitation it was possible to get information on the sample itself. Starting from this pioneering work, spectroscopic investigations have undergone an impressive evolution and applications have covered a wider a wider range. So far, besides fundamental physics, spectroscopic analysis are of direct importance in an increasing variety of applications in fields such asastrophysics, combusion, plasma physics, soft matter and, in recent years, bio-medicine. In the following pages, the main techniques of laser spectroscopy are examined: starting from discovery of the hydrogen atom spectral series, the modern application of ultrasensitive spectroscopic techniques to sample constituted by only a few molecules (single molecule spectroscopy) are discussed. Of course, this contribution surely can not be exhaustive, and the reader is referred to more general treatments of the theory and practice of spectroscopy for a more detailed treatment.


  • excitation;
  • spectroscopy;
  • absorption spectroscopy;
  • line broadening;
  • laser cooling;
  • optical pumping;
  • atomic trap