Kyoto University

Sumitomo Electric Industries, Limited

Tdk Corporation

Matsushita Electric Works, Ltd.

Japan Science and Technology Agency

Bong-Shik Song

Susumu Noda

Takashi Asano

Seiichi Takayama

Yoshihiro Akahane

Hitomichi Takano

Takashi 2-108 Katsura-Daini-Goudoushukusha Asano

The present invention intends to provide a two-dimensional photonic crystal resonator having a high Q-value. The slab-shaped bodyis provided with cyclically arranged holes. The bodyis divided into three areas-with the holesarranged with cycle distances of ain areaand ain areasand, which is smaller than a. A waveguidepassing through the three areas is formed by linearly eliminating the holes. The waveguidethus formed can propagate rays of light within a wavelength band that depends on the cycle distance of the holes. The cycle distance of the holes in the areadiffers from that of the areasand, and the wavelength band of the light propagating through the waveguide accordingly differs. Therefore, a ray of light whose wavelength is within the waveguide transmission wavelength band of the areabut outside of the waveguide transmission wavelength band of the other areasandwill be confined within the waveguide of the areaand resonate therein. Thus, the waveguide in the areafunctions as a resonator.

Two-dimensional photonic crystal resonator

An object of the present invention is to provide a two-dimensional photonic crystal which can be used for optical path changeover switches or the like to allow switching of a path. A first areaand a second areaprovided with holesandhaving a difference in the period and size are created on a bodyand a main waveguideis formed to obliquely cross a boundarybetween these areas. A branch waveguidebranched from the main waveguideinto the first areaside is also formed by using a crossing point between the main waveguideand the boundaryas a starting point. The second areais heated to change a refractive index of the body within the area, so that a frequency band which can be passed through the main waveguideof the second areais changed. Light having a specific frequency and propagated through the main waveguidefrom the first areaside is switched to be extracted from the main waveguideon the second areaside or to be extracted from the branch waveguidewithout propagating the main waveguideon the second areain response to whether or not the heating is performed.

Two-dimensional photonic crystal and optical function element using the same

In this electromagnetic wave frequency filter, an electromagnetic wave of a predetermined frequency matching a resonant frequency of a resonatoris transmitted from an input waveguideto an output waveguidethrough the resonator, and is outputted from a drop port P. This filter has an input-waveguide-side reflectorand an output-waveguide-side reflector, which reflect the electromagnetic wave of the predetermined frequency. The electromagnetic wave frequency filter satisfies the following relation:/(1&#x2212;cos &#x3b8;)&#x3c;&#x3c;,/(1&#x2212;cos &#x3b8;)=/(1&#x2212;cos &#x3b8;),&#x3b8;, &#x3b8;&#x2260;2&#x3c0;(=0, 1, . . . ),where &#x3b8;is a phase shift amount of the electromagnetic wave reflected by the input-waveguide-side reflector, &#x3b8;is a phase shift amount of the electromagnetic wave reflected by the output-waveguide-side reflector, Qis a Q-factor between the resonatorand the input waveguide, Qis a Q-factor between the resonatorand the output waveguide, and Qis a Q-factor between the resonatorand free space.

Electromagnetic wave frequency filter

Growing community of inventors

Kyoto, Japan

Bong-Shik Song