About the Authors

Charles K. Fisher

Affiliation Department of Physics, Boston University, Boston, Massachusetts, United States of America

Pankaj Mehta

pankajm@bu.edu

Affiliation Department of Physics, Boston University, Boston, Massachusetts, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: CKF PM. Analyzed the data: CKF. Wrote the paper: CKF PM.