Semiconductors are materials with properties intermediate between metals and non-conducting insulators, defined by the amount of energy needed to make an electron conductive in the material. The non-conducting electrons occupy a continuum of energy states, but two of these states (the “heavy hole” and “light hole”) are nearly identical in energy. The heavy hole is easy to observe and study, but the light hole eludes most observers.
About sophiahayesSophia is a professor of chemistry at Washington University in St. Louis. Dubbed a "chemicist" (in an accidental mis-translation by a German colleague), she has spent time as a postdoc at Technical Univ. of Dortmund (Germany), a postdoc in a chemical engineering department (jointly at UC Berkeley and LLNL), and was a graduate student at UCSB. She and her group delight in NMR spectroscopy, but have brought lasers into the lab, too, because why should the optics teams have all the fun? Hayes and her group work on optically-pumped NMR of semiconductors and spin orientation, but also on solid-state NMR studies of the structure of non-crystalline thin metal-oxide films, mesoporous materials for capture of carbon dioxide, and the structure of minerals.
Secrets of semiconductors
by Sophia Hayes