We have observed Hanle signals and n=0, p=1 parametric resonances of 23S1 metastable helium atoms in a discharge cell by optically pumping the helium atoms with a tunable Nd:LNA laser. These resonances were used to construct a sensitive magnetometer for the measurement of very small magnetic fields. Since magnetometer sensitivity is proportional to the slope of the parametric resonance signal (signal amplitude divided by linewidth), the slopes for single-line laser pumping were compared with similar quantities obtained from conventional helium lamp pumping. Laser pumping yielded 45 times greater slopes with comparable power requirements, thus establishing the potential for developing ultrasensitive resonance magnetometers using single-line laser pumping.

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Thin metal films have been fabricated by vacuum evaporation, which polarize transmitted light at near -infrared and visible wavelengths.Polarization of normal-incidence light was observed for silver, gold and copper films made by this technique. The polarizing films were produced by directing a beam of metal atoms onto the smooth surface of an optically transparent substrate at a large angle of incidence.The film structure revealed by electron-microscope examination is a dense array of parallel metal whiskers aligned opposite the direction of the incident metal atom beam.Polarization is produced by the hertzian parallel -wire effect, which is also the polarization principle of the conventional wiregrid polarizer. The resulting polarizer material can be produced in sheet form or applied as a coating to optical elements.