Knöller, Andrea
Lampa, Christian P.
Cube, Felix von
Zeng, Tingying Helen
Bell, David C.
Dresselhaus, Mildred S.
Burghard, Zaklina
Bill, Joachim
Article History
Received: 27 September 2016
Accepted: 13 December 2016
First Online: 19 January 2017
Competing interests
: The authors declare no competing financial interests.