About the Authors

Lei Zhang

stoneszhang@tsinghua.edu.cn

Affiliation Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, Tsinghua University, Beijing, China

Xiao Feng

Affiliation Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, Tsinghua University, Beijing, China

Xin Wang

Affiliation Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, Tsinghua University, Beijing, China

Changyong Liu

Affiliation Key Laboratory for Advanced Materials Processing Technology of Ministry of Education, Tsinghua University, Beijing, China

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: LZ XF CYL. Performed the experiments: XF XW. Analyzed the data: XW. Contributed reagents/materials/analysis tools: CYL. Wrote the paper: XF.