1. Biology and Biotechnology Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.
2. Physics Department, Northeastern University, Boston, MA 02115, USA.
3. School of Natural Sciences, University of California Merced, Merced, CA 94343, USA.
4. Materials Science Division, Physical and Life Sciences Directorate, Lawrence Livermore National Laboratory, Livermore, CA 94550, USA.