Marriage of two device concepts

摘要

Recent advances in semiconductor growth and processing techniques are providing unprecedented possibilities for creating artificial crystal structures with new properties. Scientists are exploiting this ability to realize innovative devices--from diodes and transistors to lasers and modulators--with specifically designed functionalities and performances. The latest milestone in this area is reported by Colombelli et al. on page 1374 of this issue. The authors have produced a "metamaterial" in whichthe electronic band structure and the electromagnetic field dispersion are tailored and matched to create a unipolar injection laser capable of vertical emission. The device combines two concepts that are enjoying vast success in fundamental and appliedsolid-state science: quantum cascade lasers and photonic crystals.