Authors: T H Kim; D Puggioni; Y Yuan; L Xie; H Zhou; N Campbell; P J Ryan; Y Choi; J-W Kim; J R Patzner; S Ryu; J P Podkaminer; J Irwin; Y Ma; C J Fennie; M S Rzchowski; X Q Pan; V Gopalan; J M Rondinelli; C B Eom Journal: Nature Date: 2016-04-20 Impact factor: 49.962