Open Access Nano Express

Optical properties of Ni and Cu nanowire arrays and Ni/Cu superlattice nanowire arrays

Yaya Zhang1, Wen Xu12*, Shaohui Xu2, Guangtao Fei2, Yiming Xiao1 and Jiaguang Hu13

Author Affiliations

1 Department of Physics, Yunnan University, Kunming, 650091, China

2 Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, 230031, China

3 Department of Math and Physics, , Wenshan, 663000, China

For all author emails, please log on.

Nanoscale Research Letters 2012, 7:569  doi:10.1186/1556-276X-7-569

Published: 15 October 2012

Abstract

In this study, Ni and Cu nanowire arrays and Ni/Cu superlattice nanowire arrays are fabricated using standard techniques such as electrochemical deposition of metals into porous anodic alumina oxide templates having pore diameters of about 50 nm. We perform optical measurements on these nanowire array structures. Optical reflectance (OR) of the as-prepared samples is recorded using an imaging spectrometer in the wavelength range from 400 to 2,000 nm (i.e., from visible to near-infrared bandwidth). The measurements are carried out at temperatures set to be 4.2, 70, 150, and 200 K and at room temperature. We find that the intensity of the OR spectrum for nanowire arrays depends strongly on the temperature. The strongest OR can be observed at about T = 200 K for all samples in visible regime. The OR spectra for these samples show different features in the visible and near-infrared bandwidths. We discuss the physical mechanisms responsible for these interesting experimental findings. This study is relevant to the application of metal nanowire arrays as optical and optoelectronic devices.

Keywords:
Nanowire array; Optical properties; Visible and near-infrared; Temperature dependence