| 摘要 |
PURPOSE:To change considerably a refractive index and to control the advance direction of light by changing the height of a barrier between a barrier layer an a well layer to obtain the effect equivalent to change of the thickness of the barrier layer practically. CONSTITUTION:When a proper reverse bias is applied across an n type electrode 25 and a p type electrode 26, the refractive index of a multilayered guantum well structure (MQW) part is raised and becomes equal to that of a waveguide. Therefore, reflection components disappear between the waveguide and the MQW part. Consequently the light incident from one side (for example, the left) of an incidence entrance 27 advances to the intersection between the waveguide in the center part of an element and an MQW switch part 23 and is transmitted or reflected totally in the MQW part in accordance with presence/absence of bias in the MQW part and is discharged from the right (in case of total transmission) or the left (in case of total reflection) of a waveguide exit 28. That is, the waveguide to which the light is discharged is switched. An optical waveguide 24 is set to a high resistance to reduce the loss of light based on carrier absorption. |
