Defect Control of Conventional and Anomalous Electron Transport at Complex Oxide Interfaces
Abstract
Using low-temperature electrical measurements, the interrelation between electron transport, magnetic properties, and ionic defect structure in complex oxide interface systems is investigated, focusing on NdGaO3/SrTiO3 (100) interfaces. Field-dependent Hall characteristics (2–300 K) are obtained for samples grown at various growth pressures. In addition to multiple electron transport, interfacial magnetism is tracked exploiting the anomalous Hall effect (AHE). These two properties both contribute to a nonlinearity in the field dependence of the Hall resistance, with multiple carrier conduction evident below 30 K and AHE at temperatures ≲10 K. Considering these two sources of nonlinearity, we suggest a phenomenological model capturing the complex field dependence of the Hall characteristics in the low-temperature regime. Our model allows the extraction of the conventional transport parameters and a qualitative analysis of the magnetization. The electron mobility is found to decrease systematically with increasing growth pressure. This suggests dominant electron scattering by acceptor-type strontium vacancies incorporated during growth. The AHE scales with growth pressure. In conclusion, the most pronounced AHE is found at increased growth pressure and, thus, in the most defective, low-mobility samples, indicating a correlation between transport, magnetism, and cation defect concentration.
- Authors:
- Publication Date:
- Research Org.:
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States)
- Sponsoring Org.:
- USDOE
- OSTI Identifier:
- 1312063
- Alternate Identifier(s):
- OSTI ID: 1312560
- Grant/Contract Number:
- AC02-76SF00515; GBMF4415; N00014-12-1-0976
- Resource Type:
- Published Article
- Journal Name:
- Physical Review. X
- Additional Journal Information:
- Journal Name: Physical Review. X Journal Volume: 6 Journal Issue: 3; Journal ID: ISSN 2160-3308
- Publisher:
- American Physical Society
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 74 ATOMIC AND MOLECULAR PHYSICS
Citation Formats
Gunkel, F., Bell, Chris, Inoue, Hisashi, Kim, Bongju, Swartz, Adrian G., Merz, Tyler A., Hikita, Yasuyuki, Harashima, Satoshi, Sato, Hiroki K., Minohara, Makoto, Hoffmann-Eifert, Susanne, Dittmann, Regina, and Hwang, Harold Y. Defect Control of Conventional and Anomalous Electron Transport at Complex Oxide Interfaces. United States: N. p., 2016.
Web. doi:10.1103/PhysRevX.6.031035.
Gunkel, F., Bell, Chris, Inoue, Hisashi, Kim, Bongju, Swartz, Adrian G., Merz, Tyler A., Hikita, Yasuyuki, Harashima, Satoshi, Sato, Hiroki K., Minohara, Makoto, Hoffmann-Eifert, Susanne, Dittmann, Regina, & Hwang, Harold Y. Defect Control of Conventional and Anomalous Electron Transport at Complex Oxide Interfaces. United States. https://doi.org/10.1103/PhysRevX.6.031035
Gunkel, F., Bell, Chris, Inoue, Hisashi, Kim, Bongju, Swartz, Adrian G., Merz, Tyler A., Hikita, Yasuyuki, Harashima, Satoshi, Sato, Hiroki K., Minohara, Makoto, Hoffmann-Eifert, Susanne, Dittmann, Regina, and Hwang, Harold Y. Tue .
"Defect Control of Conventional and Anomalous Electron Transport at Complex Oxide Interfaces". United States. https://doi.org/10.1103/PhysRevX.6.031035.
@article{osti_1312063,
title = {Defect Control of Conventional and Anomalous Electron Transport at Complex Oxide Interfaces},
author = {Gunkel, F. and Bell, Chris and Inoue, Hisashi and Kim, Bongju and Swartz, Adrian G. and Merz, Tyler A. and Hikita, Yasuyuki and Harashima, Satoshi and Sato, Hiroki K. and Minohara, Makoto and Hoffmann-Eifert, Susanne and Dittmann, Regina and Hwang, Harold Y.},
abstractNote = {Using low-temperature electrical measurements, the interrelation between electron transport, magnetic properties, and ionic defect structure in complex oxide interface systems is investigated, focusing on NdGaO3/SrTiO3 (100) interfaces. Field-dependent Hall characteristics (2–300 K) are obtained for samples grown at various growth pressures. In addition to multiple electron transport, interfacial magnetism is tracked exploiting the anomalous Hall effect (AHE). These two properties both contribute to a nonlinearity in the field dependence of the Hall resistance, with multiple carrier conduction evident below 30 K and AHE at temperatures ≲10 K. Considering these two sources of nonlinearity, we suggest a phenomenological model capturing the complex field dependence of the Hall characteristics in the low-temperature regime. Our model allows the extraction of the conventional transport parameters and a qualitative analysis of the magnetization. The electron mobility is found to decrease systematically with increasing growth pressure. This suggests dominant electron scattering by acceptor-type strontium vacancies incorporated during growth. The AHE scales with growth pressure. In conclusion, the most pronounced AHE is found at increased growth pressure and, thus, in the most defective, low-mobility samples, indicating a correlation between transport, magnetism, and cation defect concentration.},
doi = {10.1103/PhysRevX.6.031035},
journal = {Physical Review. X},
number = 3,
volume = 6,
place = {United States},
year = {Tue Aug 30 00:00:00 EDT 2016},
month = {Tue Aug 30 00:00:00 EDT 2016}
}
https://doi.org/10.1103/PhysRevX.6.031035
Web of Science
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