| 摘要 |
PURPOSE:To improve the switching efficiency by specifying a relation of refractive indexes of the lower clad, a core and the upper clad. CONSTITUTION:When refractive indexes of the lower clad 1, a core 2 and the upper clad 3 are denoted as n1 - n3, respectively, a relation of n2>n3>n1 is formed among n1 - n3. Subsequently, when a current is injected from the upper clad 3 in such a state, a single mode conversion in the path width direction is realized, and simultaneously, a refractive index variation in the path width direction becomes larger than conventional. In such a way, as soon as the single mode conversion is realized, the refractive index variation caused by injecting a current advances with high efficiency. |
