ABSTRACT
We demonstrate that holographic information can be stored in Eu(3+)-doped alkali aluminosilicate glasses. The holograms were developed by a two-beam mixing configuration with a write-beam wavelength (465.8 nm) corresponding to the (7)F(0) ? (5)D(0) transition of the Eu(3+) ions. The images were reconstructed either with the wavelength used to record them or with wavelengths below this transition (543.5 and 632.8 nm). We stored clear holographic images using a total writing power of 5 mW and an exposure time of 20 s. In addition, clear holograms were recorded with an exposure time of 200 ms when 100 mW of the writing power was used. The exposure time and the writing power required to obtain clear holographic images are dependent on the Eu(3+) concentration.
ABSTRACT
We measure the refractive index of materials using a CCD camera with a laser beam profiler in the familiar Brewster's angle experiment. This allows us to isolate quickly and accurately the Brewster's angle close to the resolution of the sample rotation stage. The uncertainty in the index of refraction measurement is similar to that of the standard minimum-deviation technique.