Ndukaife, Justus C.
Kildishev, Alexander V.
Nnanna, Agbai George Agwu
Shalaev, Vladimir M.
Wereley, Steven T.
Boltasseva, Alexandra
Article History
Received: 9 May 2015
Accepted: 24 September 2015
First Online: 2 November 2015
Competing interests
: The authors declare no competing financial interests.