Hosang Yoon and Donhee Ham, Harvard University (image) Harvard University Share Print E-Mail Caption Hosang Yoon, Ph.D. '14, and Prof. Donhee Ham have measured the collective mass of electrons in graphene. Credit Photo by Eliza Grinnell, Harvard SEAS. Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.