G. Schmerber

Absence of ferromagnetism in Al-doped Zn0.9Co0.10O diluted magnetic semiconductors

A 0.5% Al-doped Zn0.895Co0.100O polycrystalline powder was synthesized by the co-precipitation method. Raman spectroscopy revealed that divalent cobalt ions were substituted for Zn2+ ions into the ZnO matrix and that Al ions activate additional modes which are nonspecific to the dopant. These additional modes disappear after annealing at 1373K for 1h under Ar flow. We suggest that the electrical dopant becomes active in substitutional sites after annealing. Resistance measurements confirm that free carriers were created in our sample. Nevertheless, the sample shows the same magnetic properties: a mixture of paramagnetism and antiferromagnetism.

Paramagnetism of the Co sublattice in ferromagnetic Zn1 xCoxO films

Using the spectroscopies based on x-ray absorption, we have studied the structural and magnetic properties of

Extrinsic origin of ferromagnetism in ZnO and Zn0.9Co0.1O magnetic semiconductor films prepared by sol-gel technique

{\mathrm{Zn}}_{1\ensuremath{-}x}{\mathrm{Co}}_{x}\mathrm{O}

Room-temperature ferromagnetism in Zn1−xCoxO magnetic semiconductors prepared by sputtering

films (

Pure paramagnetic behavior in Mn-doped ZnO semiconductors

x=0.1

Structural, optical, and electrical properties of Yb-doped ZnO thin films prepared by spray pyrolysis method

and 0.25) produced by reactive magnetron sputtering. These films show ferromagnetism with a Curie temperature

Structural and photoluminescence properties of ZnO thin films prepared by sol-gel process

{T}_{C}

Room temperature ZnO growth by rf magnetron sputtering on top of photoactive P3HT: PCBM for organic solar cells

above room temperature in bulk magnetization measurements. Our results show that the Co atoms are in a divalent state and in tetrahedral coordination, thus substituting Zn in the wurtzite-type structure of ZnO. However, x-ray magnetic circular dichroism at the

Optical properties of ZnO thin films prepared by sol-gel process

\mathrm{Co}\phantom{\rule{0.2em}{0ex}}{L}_{2,3}

Correlation of structural properties with energy transfer of Eu-doped ZnO thin films prepared by sol-gel process and magnetron reactive sputtering.

edges reveals that the