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Atomic Spectroscopy Group: Laser Spectroscopy

The laser spectroscopy lab has a number of tools at its disposal. A ring dye laser with intracavity doubling capability, two linear dye lasers, an argon ion laser with visible and UV optics, and a krypton ion laser with red and UV optics are used to probe the atomic and molecular transitions.

To measure the energy of the laser light, we have two tools available. Our Michelson wavemeter has an absolute resolution of about 0.0015 cm-1 (~ 50 MHz). Typically, we use the Michelson to tune the dye lasers and to provide a seed value for the high resolution Fabry-Pérot wavemeter. Our Fabry-Pérot wavemeter has an ultimate resolution of a few parts in 109, enabling us to measure photon energies to better than 1 MHz.

Our capabilities are limited by the available laser dyes and optics sets. In the figure below, the hashed regions show the available wavelength ranges that we currently have for our ring dye laser. Intracavity doubling extends the range into the UV for a few of the dyes.

Available Laser Dye Sets
Available Ring Laser Dyes

Fabry Perot Wavemeter
Fabry-Pérot Wavemeter

Recent Projects:

  • Laser Spectroscopy Study of Li

    We have undertaken a detailed study of the structure of atomic lithium. Many of the older measurements are of insufficient precision to test recent developments in atomic theory.

  • Optogalvanic Reference Lines in U and Th

    We have measured a series of lines in the deep red and near infrared for U and Th using optogalvanic spectroscopy of commercial hollow cathode lamps. These lines are well suited for wavelength references in the part of the spectrum where it is difficult to observe I2 transitions.

    For technical questions contact: