[1]Department of Physics, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville AR 72 701, USA [2]Department of Electrical Engineering, University of Arkansas, Fayetteville AR 72701, USA [3]Center of Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock AR 72204, USA;
[1]Department of Physics, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville AR 72 701, USA [2]Department of Electrical Engineering, University of Arkansas, Fayetteville AR 72701, USA [3]Center of Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock AR 72204, USA;
[1]Department of Physics, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville AR 72 701, USA [2]Department of Electrical Engineering, University of Arkansas, Fayetteville AR 72701, USA [3]Center of Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock AR 72204, USA;
[1]Department of Physics, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville AR 72 701, USA [2]Department of Electrical Engineering, University of Arkansas, Fayetteville AR 72701, USA [3]Center of Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock AR 72204, USA;
[1]Department of Physics, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville AR 72 701, USA [2]Department of Electrical Engineering, University of Arkansas, Fayetteville AR 72701, USA [3]Center of Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock AR 72204, USA;
[1]Department of Physics, Institute for Nanoscience and Engineering, University of Arkansas, Fayetteville AR 72 701, USA [2]Department of Electrical Engineering, University of Arkansas, Fayetteville AR 72701, USA [3]Center of Integrative Nanotechnology Sciences, University of Arkansas at Little Rock, Little Rock AR 72204, USA;