Energy-dependent hot electron transport across a spin-valve

Abstract

Advaiiml Keseardi Laboratory, rosluba Corporation, Kawasaki. Kaiiagav a. 2 10. .lapdii ilhutuad -Hot electron transport across an FeiAulFe spin w l v e W:IS examined by mea3uring a collector current of a hot electron transibtor which w:is composed of an AIIALO, emitter, thc spin-valve base and :in irSi collector. The collector C U I rent changed morc than 200"/0 under ilppliciitlon of magnetic field. The magnitude of this change dccreiised monotonously w i t h emittcr voltiige, and no :momaly n u observed at the iolt,lge (-1.5 V) corresponding to the sharp PCiIlC in the density of states of the minority spin bands in Fe

Bias voltage and temperature dependence of hot electron magnetotransport

“…5 in the Ref. [5] shows very broad features. There may be several factors contributing to broaden the hysteresis curve.…”

“…Theoretical studies to account for the experimental observation have been also presented by the authors of the Ref. [5][6][7][8]. They claim that the inelastic scattering contributes to reduce the magnetoresistance above 1.5 eV, and the elastic scattering enhances the magnetoresistance around 1 eV.…”

“…Unlike large volume of data in the MTJ, only few data are available in the hot electron magnetotransport study. In the issue of energy dependence of hot electron magnetotransport, it has been presented experimentally by Mizushima et el [5]. Theoretical studies to account for the experimental observation have been also presented by the authors of the Ref.…”

“…5 in the Ref. [5] shows the hysteresis curve of the sample. One can easily understand that the switching of the ferromagnetic layers is not well defined.…”

“…For instance, the thickness of ferromagnetic layer is too thin, so that the sample may have locally different coercivity field (the thickness of Fe layers was 10Å and 15Å in the spin-valve base of Ref. [5]) . Therefore, it may be very difficult to extract essential physics when one explores the hot electron magnetotransport based on the data of Ref.…”