We are conducting a unified research of fabrication, theoretical analysis, and evaluation for photonic crystals, with aiming to overcome various limitations in the today’s photonics technologies and to realize breakthroughs in photonic information processing.
We are developing an artificial periodic structure called a photonic crystal employing the state-of-the-art semiconductor nano-fabrication technologies for silicon and other semiconductors. Recently, we have realized ultrasmall optical resonators with ultrastrong light confinement by photonic crystals. In comparison with electronics technology, photonics technology is known to be good at handling ultrafast and broadband information processing, but it has a drawback in confining signal in a small space. The optical resonator we developed can store light within a wavelength-scale space for over a nanosecond. Such a resonator enables various ways of controlling light which have been impossible by conventional methods. As a example, we have recently demonstrated generation of slowlight in which the traveling speed of light is slowed down by a factor of 50, 000 using our ultrasmall resonators. This slowlight will be applied for signal buffering or enhancement of interactions in a photonic chip. Moreover, we have succeeded in developing ultrasmall photonic bit memories with extremely small power consumption, in which we have fully exploited theoretically-expected enhancement of light-matter interaction in our ultrasmall resonators. These technologies we are developing are suited for large-scale integration in a semiconductor chip, and we are currently continuing our research towards future densely-integrated photonic processing chips.