Prof. John D Joannopoulos

The research of Professor Joannopoulos spans two major directions. The first is devoted to creating a realistic and microscopic theoretical description of the properties of material systems. His approach is fundamental to predicting geometric, electronic and dynamical structure, ab-initio -- that is, given only the atomic numbers of the constituent atoms as experimental input. Ab-initio investigations are invaluable because they can stand on their own, complement experimental observations, and probe into regimes inaccessible to experiment. Examples of recent work include the elucidation of electron transport in water and the deliberate computer design of a new semiconductor alloy for use as a novel optoelectronic material.

The second major direction involves the development of a new class of materials called photonic crystals, which are designed to effect the properties of photons in much the same way that semiconductors effect the properties of electrons. These materials provide a new dimension in the ability to control and mold the flow of light. Current efforts include the design of novel channel drop microfilters, high efficiency LEDs, low threshold microlasers, and low-loss waveguide bends and intersections.