Techniques for Band Gap Engineering vary, including doping, the introduction of impurities into a semiconductor to alter its electrical properties; strain engineering, where stress is applied to ...

By contrast, conductors have a band gap that is narrow to nonexistent. Semiconductors are sometimes considered to be insulators with narrow band gaps. For a visual explanation of N-type versus P ...

That's the kind of technology that researchers at Kyoto University have developed for the band gap of semiconductor materials. The work is published in the journal Computational Materials Science.