Editorial

This year marks the 100th anniversary since Albert Einstein proposed the idea of stimulated emission of radiation. 1 While this concept is critical to the understanding of the equilibrium of black-body radiation, 2 it has led to the invention of the maser (microwave amplification by stimulated emission of radiation) incidentally, the US Defense Advanced Research Projects Agency announced a program -Enabling Extreme New Designs for Optics and Imagersthat aims to develop highly portable, miniaturized and efficient devices for advanced imaging applications. It is anticipated that this program will lead to enhanced two-(2D) and three-dimensional (3D) optoelectronic and photonic structures with multi-function capability of operation in the desired range of wavelengths. This project is an excellent case of design-optimization-process-properties-performance in band-gap engineering, optical and photonic materials, structures and networks and should help to transition devices such as photonic crystals 9,10 and quantum dots