He represented lead niobate by A1 + xNb2O6 where the A site is an ion ( usually lead ) and he found that the upper limit of x in his representation was about 0.15 and a low limit between " 0.07 and " 0.08.
42.
Two types of devices are currently common : " frequency doublers, " often based on lithium niobate ( LN ), lithium tantalate ( LT ), potassium titanyl phosphate ( KTP ) or lithium triborate ( LBO ), and " frequency triplers " typically made of potassium dihydrogen phosphate ( KDP ).
43.
Unlike electronic integration where silicon is the dominant material, system photonic integrated circuits have been fabricated from a variety of material systems, including electro-optic crystals such as lithium niobate, silica on silicon, Silicon on insulator, various polymers and semiconductor materials which are used to make semiconductor lasers such as GaAs and InP . The different material systems are used because they each provide different advantages and limitations depending on the function to be integrated.
