24 research outputs found
Spintronics: Fundamentals and applications
Spintronics, or spin electronics, involves the study of active control and
manipulation of spin degrees of freedom in solid-state systems. This article
reviews the current status of this subject, including both recent advances and
well-established results. The primary focus is on the basic physical principles
underlying the generation of carrier spin polarization, spin dynamics, and
spin-polarized transport in semiconductors and metals. Spin transport differs
from charge transport in that spin is a nonconserved quantity in solids due to
spin-orbit and hyperfine coupling. The authors discuss in detail spin
decoherence mechanisms in metals and semiconductors. Various theories of spin
injection and spin-polarized transport are applied to hybrid structures
relevant to spin-based devices and fundamental studies of materials properties.
Experimental work is reviewed with the emphasis on projected applications, in
which external electric and magnetic fields and illumination by light will be
used to control spin and charge dynamics to create new functionalities not
feasible or ineffective with conventional electronics.Comment: invited review, 36 figures, 900+ references; minor stylistic changes
from the published versio
Electrical and photoluminescence properties of bulk GaAs after surface gettering
The successful results on surface gettering of background impurities and defects in 1.6 mm thick (111) GaAs wafers have been obtained. For the gettering, the wafers were coated by a 1000 Ă
thick yttrium film either on one side or on both sides followed by a heat treatment. It has allowed the electron concentration to decrease from (1â2)ÂŽ10 15 cm -3 down to 10 8 â10 10 cm -3 and the mobility to increase from 1500â2000 cm 2 V -1 s -1 up to 7000 cm 2 V -1 s -1 at 300 K. The distribution profiles of the electron concentration and of the hole effective lifetime throughout the wafer thickness as well as photoluminescence spectra at 2 K have been presented