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300 K Ferromagnetic Magnetic Circular Dichroism in Co2+-doped ZnO Activated by Shallow Donors

Kevin R. Kittilstved·Jialong Zhao·William K. Liu·J. Daniel Bryan·Daniel R. Gamelin
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Abstract

Cobalt-doped ZnO (Co2+:ZnO) films were studied by magnetic circular dichroism (MCD) spectroscopy. A broad 300 K ferromagnetic MCD signal was observed between 1.4 and 4.0 eV after introducing shallow donor states by exposure of paramagnetic Co2+:ZnO films to zinc vapor. The new sub-bandgap ferromagnetic MCD intensity is attributed to low-energy photoionization transitions originating from a spin-split donor impurity band in ferromagnetic Co2+:ZnO.

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Kevin R. Kittilstved, Jialong Zhao, William K. Liu, J. Daniel Bryan, Daniel R. Gamelin. 2005-07-05. 300 K Ferromagnetic Magnetic Circular Dichroism in Co2+-doped ZnO Activated by Shallow Donors. https://arxiv.org/abs/cond-mat/0507121

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