Author Affiliations

F. Ritzkowsky,^1,* M. R. Bionta,^2,* M. Turchetti,^2,* Y. Yang,² W. P. Putnam,³ K. K. Berggren,² F. X. Kärtner,¹ and P. D. Keathley^2,**

¹Deutsches Elektronen Synchrotron (DESY) & Center for Free-Electron Laser Science, Notkestraße 85, 22607 Hamburg, Germany

²Research Laboratory of Electronics, MIT, 77 Massachusetts Avenue, Cambridge, MA 02139, USA

³Department of Electrical and Computer Engineering, University of California, Davis, 1 Shields Ave, Davis, CA 95616, USA

^*These authors contributed equally to this work

^** pdkeat2@mit.edu