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Spin Polarization of Injected Electrons



William F. Egelhoff Jr., Mark D. Stiles, David P. Pappas, Daniel T. Pierce, J M. Byers, J M. Johnson, B T. Jonker, S F. Alvarado, J F. Gregg, J A. Bland, R Buhrman


A recent paper in Science made the claim of 92% polarization for the injection spin polarized electrons from a Ni scanning tunneling microscopy (STM) tip into GaAs(110). Actually they state their result as 92% efficiency for the injection of 100% importance for the emerginging field of Apintronics. If true, it would suggest that the field is rapidly closing in on the key goal of 100% efficiency. However, we wish to inform the Science readership that the claim is by no means substantiated by a close examination of the work, and in fact serious errors in the analysis imply that the actual polarization was much less than 92%. Since the tip is not 100% spin polarized, it makes no sense to break this polarization into a tip polarization times an efficiency.
No. 5571


gallium arsnide tunneling nickel, spin polarization


Egelhoff, W. , Stiles, M. , Pappas, D. , Pierce, D. , Byers, J. , Johnson, J. , Jonker, B. , Alvarado, S. , Gregg, J. , Bland, J. and Buhrman, R. (2002), Spin Polarization of Injected Electrons, Science (Accessed July 20, 2024)


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Created May 1, 2002, Updated February 17, 2017