Optical Pumping in Chromium

Optical pumping in chromium provides the foundation for much of the laser manipulation that is done in our work. In addition to developing this technology for the current work, we have also made use of it to study spin-polarized electron scattering from optically pumped chromium [EPG pub# 626].

For reference, below are some data relevant to the optical pumping of chromium

Mass: 51.996 a.u.

Ground state: (Ar)3d⁵4s¹ (⁷S₃)

Charge: 24

Melting point: 1875 °C

Density: 7.2 g/cc

Typical oven temperature for an atom beam: 1500 - 1650°C (material sublimes, without melting)

Natural isotope abundance:

83.8% ⁵²Cr (I=0);

9.5% ⁵³Cr (I=3/2);

4.3% ⁵⁰Cr (I=0);

2.4% ⁵⁴Cr (I=0)

Spectrum, showing optical pumping transition:

Optical pumping transition:

⁷S₃ - ⁷P^o₄ 425.43 nm: (air),

or 425.55 nm: (vacuum)

Natural linewidth: 5 MHz
Saturation intensity: 8.5 mW/cm²



Spin-resolved Superelastic Electron Scattering from Laser Excited Chromium Atoms
Optical State-Preparation of Atoms


Jabez J. McClelland - NIST


Robert Scholten - University of Melbourne

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Online: May 1996
Last Updated: February 2008

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