| 摘要 |
<p>A non-linear optical device such as a frequency changer, parametric amplifier or mixer comprises a stack of grating layers (1, 2, 3 )of non-linear optical material. Each grating layer comprises at least one grating (5) and is bonded in spaced relation to adjacent grating layers (4), preferably by a glass consisting essentially of germanium, arsenic, selenium and a relatively high proportion of tellurium. As described, the gratings (5) in a layer are spaced and formed by periodic electrical poling. The periodicity in adjacent layers may be the same or different. The layers may be of material useful in the infra-red. The layers may be formed of GaAs, ZnSe, ZnGeP2, lithium niobate, potassium, titanyl phosphate of rubidium titanyl arsenate.</p> |
