Abstract
There has been much interest in the injection and detection of spin-polarized carriers in semiconductors for the purposes of developing novel spintronic devices. Here we report the electrical injection and detection of spin-polarized carriers into Nb-doped strontium titanate single crystals and La-doped strontium titanate epitaxial thin films using MgO tunnel barriers and the three-terminal Hanle technique. Spin lifetimes of up to ∼100 ps are measured at room temperature and vary little as the temperature is decreased to low temperatures. However, the mobility of the strontium titanate has a strong temperature dependence. This behaviour and the carrier doping dependence of the spin lifetime suggest that the spin lifetime is limited by spin-dependent scattering at the MgO/strontium titanate interfaces, perhaps related to the formation of doping induced Ti 3+. Our results reveal a severe limitation of the three-terminal Hanle technique for measuring spin lifetimes within the interior of the subject material. © 2013 Macmillan Publishers Limited. All rights reserved.
Original language | English (US) |
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Journal | Nature Communications |
Volume | 4 |
Issue number | 1 |
DOIs | |
State | Published - Jul 8 2013 |
Externally published | Yes |
Bibliographical note
KAUST Repository Item: Exported on 2020-10-01Acknowledgements: We acknowledge partial support for this work from the MURI program of the Army Research Office (Grant no. W911-NF-09-1-0398) and the King Abdullah University of Science and Technology (KAUST), and thank Professor Aurelien Manchon, KAUST, for useful discussions.
This publication acknowledges KAUST support, but has no KAUST affiliated authors.