Photonic Systems Brown Bag Seminar

Thursday, February 17, 2005, at 12 noon                                RLE Haus Room, 36-428

A 3D Photonic Crystal with Designed Point Defects at Telecommunication Wavelengths

Minghao Qi

Photonic crystals (PhCs) offer unprecedented opportunities for miniaturizing and integrating a variety of conventional bulky optical devices.  A PhC is usually a composite of two materials with high and low dielectric constants (e.g. silicon and air), arranged periodically in space.  For applications at telecommunication wavelengths, the periodicity is in the submicron range and individual features may even be a t nanometer length scale.  The majority of current research has been focused on 2D periodic PhCs due to ease of fabrication.  However, fundamental limitations, such as radiation losses in the third dimension, make 2D structures potentially unsuitable for a number of applications.  3D PhCs, though free from such limitations, have proved to be extremely challenging to fabricate.  In particular, intentional "defects" in 3D PhCs on an optical wavelength scale, which are the building blocks of future ultra-compact devices, have not been achieved until recently. In this talk I will report the demonstration of the first intentional point-defects, in a new class of 3D PhCs that are particularly well suited for optical integration.  Optical measurements are in excellent agreement with high-accuracy numerical simulations.  I will also give a very preliminary outlook on unique applications that 3D PhCs enable.  An interesting direction might be the miniaturization of femtosecond lasers.