Patent ID: 7706653

Claim:
An optical waveguide device, comprising: a core having a stacked structure of 2N−1 layers including a plurality of first thin film layers and one or a plurality of second thin film layers, N being an integer equal to or greater than two, each layer alternately being one of the first thin film layers and one of the second thin film layer or layers, a lowermost layer being one of the first thin film layers, an uppermost layer being another one of the first thin film layers, whereby the core has N first thin film layers and N−1 second thin film layer or layers, each first thin film layer having a finite width and thickness and being formed of a first material having a relatively high electric conductivity, each second thin film layer being formed of a second material having a lower electric conductivity than the material forming the first thin film layers, two adjacent first thin film layers being disposed to provide interaction of surface plasmons; and a clad disposed around the core and formed of a material having a lower electric conductivity than the material forming the first thin film layers and a higher refractive index than the material forming the second thin film layer or layers, an entire bottom surface of the lowermost layer and an entire top surface of the uppermost layer being covered by the clad, wherein each first thin film layer has a width that is smaller than a width of the second thin film layers, such that each second thin film layer that covers a top surface of an adjacent first thin film layer entirely covers both side surfaces of the adjacent first thin film layer.