| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical modulator including a curved slot waveguide with improved modulation efficiency.SOLUTION: An optical modulator 10 has a waveguide structure comprising: a waveguide pair 122, 124 formed of a high refractive index medium having refractive index higher than a predetermined refractive index and arranged parallel to one another; and a slot 120 arranged between the waveguide pair 122, 124, having electrooptic effect, and filled with a low refractive index medium having refractive index lower than the predetermined refractive index. At least a part of the waveguide structure includes a curved part curved in one direction in a plane parallel or substantially parallel to a plane including the waveguide pair 122, 124. The optical modulator 10 further comprises: a ring waveguide 12 formed so that, among the waveguide pair 122, 124 in the curved part, the waveguide 124 at a curved direction side has a wider width than that of the waveguide 122 at an opposite direction side to the curved direction; and electric field application means 18, 20 for applying electric field to the slot 120 in a direction intersecting with light propagating through the slot 120. |
