Author contributions
Yann
Hautier and Andy Hector conceived and designed the experiment at the
University of Zurich and Pengfei Zhang, Xiaolong Zhou and Guozhen Du at
Lanzhou University. Yann Hautier performed the experiment at the
University of Zurich and Pengfei Zhang, Xiaolong Zhou and Zhi Guo at
Lanzhou University. Pengfei Zhang and Yann Hautier analyzed the data
with input from all authors. Pengfei Zhang and Yann Hautier wrote the
manuscript with inputs from all
authors.