His research focus is on electromagnetic and optical micro/nanoscale metadevices. He has been actively involved in many multidisciplinary governmental sponsored projects, such as Air Force of Scientific Research, Air Force Research Laboratory, National Science Foundation, U.S. Office of Naval Research, and Defense Advanced Research Projects Agency, as well as industry-sponsored projects. His group conducts research in the areas of multiphysics multiscale computational models and functional RF and photonic components and systems. He is listed in Who's Who in Science and Engineering, in America, and in the World. He is the holder of one U.S. patent and has authored and co-authored more than 100 technical journal articles and conference papers,Dr. Mosallaei is a full member of URSI, and member of the American Association for the Advancement of Science. He was the recipient of student prize paper awards in AP-S 2000, 01, 03, and 05 along with his students, the URSI Young Scientist Award in 2001, and RMTG award in 2002. His student won the Northeastern Dissertation-Writing Fellowship Award in 2010.