A paper published in Optica https://www.osapublishing.org/optica/abstract.cfm?uri=optica-7-8-924 reports the first electrically-injected GeSn MWIR lasers epitaxially grown on Si substrates. It is authored by our group alumnus Prof. Shui-Qing(Fisher) Yu at University of Arkansas and his collaborators from our group, Wilkes University, Dartmouth College, UMASS Boston and Arktonics LLC.