Resolving unoccupied electronic states with laser ARPES in bismuth-based cuprate superconductors

Tristan L. Miller,1,2 Minna Ärrälä,3 Christopher L. Smallwood,1,2 Wentao Zhang,1,2 Hasnain Hafiz,4 Bernardo Barbiellini,4 Koshi Kurashima,5 Tadashi Adachi,6 Yoji Koike,5 Hiroshi Eisaki,7 Matti Lindroos,3 Arun Bansil,4 Dung-Hai Lee,2 and Alessandra Lanzara1,2,* 1Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA 2Department of Physics, University of California, Berkeley, California 94720, USA 3Department of Physics, Tampere University of Technology, Post Office Box 692, FIN-33101 Tampere, Finland 4Department of Physics, Northeastern University, Boston, Massachusetts 02115, USA 5Department of Applied Physics, Tohoku University, Sendai 980-8579, Japan 6Department of Engineering and Applied Sciences, Sophia University, Tokyo 102-8554, Japan 7Electronics and Photonics Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki 305-8568, Japan (Received 23 December 2014; revised manuscript received 27 January 2015; published 13 February 2015)