Evidence for surface states in pristine and Co-doped ZnO nanostructures: magnetization and nonlinear optical studies.
An unexpected presence of ferromagnetic (FM) ordering in nanostructured ZnO has been reported previously. Recently, from our detailed magnetization studies and ab initio calculations, we attributed this FM ordering in nanostructured ZnO to the presence of surface states, and a direct correlation between the magnetic properties and crystallinity of ZnO was observed. In this study, through a systematic sample preparation of both pristine and Co-doped ZnO nanostructures, and detailed magnetization and nonlinear optical (NLO) measurements, we confirm that the observed FM ordering is due to the presence of surface states.
Department of Physics and Astronomy, Clemson University, Clemson, SC 29634, USA.
Ramakrishna
R
Podila
Benoy
B
Anand
J Palmer
JP
West
Reji
R
Philip
S Siva Sankara
SS
Sai
Jian
J
He
Malcolm
M
Skove
Shiou-Jyh
SJ
Hwu
Sumanta
S
Tewari
Apparao M
AM
Rao
D003035:Cobalt / Q000737:chemistry*; D003198:Computer Simulation; D003460:Crystallization / Q000379:methods; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008956:Models, Chemical; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods; D017711:Nonlinear Dynamics; D010316:Particle Size; D012031:Refractometry; D013499:Surface Properties; D015034:Zinc Oxide / Q000737:chemistry*
D046911:Macromolecular Substances; D003035:Cobalt; D015034:Zinc Oxide