Chen, Changyao
Deshpande, Vikram V.
Koshino, Mikito
Lee, Sunwoo
Gondarenko, Alexander
MacDonald, Allan H.
Kim, Philip
Hone, James
Article History
Received: 8 July 2015
Accepted: 27 October 2015
First Online: 7 December 2015
Change Date: 25 February 2016
Change Type: Erratum
Change Details: In the version of this Letter originally published, dashed lines indicating where the model is not expected to be accurate were omitted from the lower two panels in Fig. 4a. This has been corrected in all versions of the Letter.
Competing interests
: The authors declare no competing financial interests.