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Title: Origin of the net magnetic moment in LaCoO 3

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review B
Additional Journal Information:
Journal Volume: 97; Journal Issue: 2; Related Information: CHORUS Timestamp: 2018-01-19 10:06:28; Journal ID: ISSN 2469-9950
American Physical Society
Country of Publication:
United States

Citation Formats

Kaminsky, G. M., Belanger, D. P., Ye, F., Fernandez-Baca, J. A., Wang, J., Matsuda, M., and Yan, J. -Q. Origin of the net magnetic moment in LaCoO 3. United States: N. p., 2018. Web. doi:10.1103/PhysRevB.97.024418.
Kaminsky, G. M., Belanger, D. P., Ye, F., Fernandez-Baca, J. A., Wang, J., Matsuda, M., & Yan, J. -Q. Origin of the net magnetic moment in LaCoO 3. United States. doi:10.1103/PhysRevB.97.024418.
Kaminsky, G. M., Belanger, D. P., Ye, F., Fernandez-Baca, J. A., Wang, J., Matsuda, M., and Yan, J. -Q. 2018. "Origin of the net magnetic moment in LaCoO 3". United States. doi:10.1103/PhysRevB.97.024418.
title = {Origin of the net magnetic moment in LaCoO 3},
author = {Kaminsky, G. M. and Belanger, D. P. and Ye, F. and Fernandez-Baca, J. A. and Wang, J. and Matsuda, M. and Yan, J. -Q.},
abstractNote = {},
doi = {10.1103/PhysRevB.97.024418},
journal = {Physical Review B},
number = 2,
volume = 97,
place = {United States},
year = 2018,
month = 1

Journal Article:
Free Publicly Available Full Text
This content will become publicly available on January 19, 2019
Publisher's Accepted Manuscript

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  • Epimore » taxial La 1.85 Sr 0.15 CuO 4 / La 2 / 3 Ca 1 / 3 MnO 3 (LSCO/LCMO) superlattices (SL) on (001)- oriented LaSrAlO 4 substrates have been grown with pulsed laser deposition (PLD) technique. Their structural, magnetic and superconducting properties have been determined with in-situ reflection high energy electron diffraction (RHEED), x-ray diffraction, specular neutron reflectometry, scanning transmission electron microscopy (STEM), electric transport, and magnetization measurements. We find that despite the large mismatch between the in-plane lattice parameters of LSCO (a = 0.3779 nm) and LCMO (a = 0.387 nm) these superlattices can be grown epitaxially and with a high crystalline quality. While the first LSCO layer remains clamped to the LSAO substrate, a sizeable strain relaxation occurs already in the first LCMO layer. The following LSCO and LCMO layers adopt a nearly balanced state in which the tensile and compressive strain effects yield alternating in-plane lattice parameters with an almost constant average value. No major defects are observed in the LSCO layers, while a significant number of vertical antiphase boundaries are found in the LCMO layers. The LSCO layers remain superconducting with a relatively high superconducting onset temperature of T c onset ≈ 36 K. The macroscopic superconducting response is also evident in the magnetization data due to a weak diamagnetic signal below 10 K for H ∥ ab and a sizeable paramagnetic shift for H ∥ c that can be explained in terms of a vortex-pinning-induced flux compression. The LCMO layers maintain a strongly ferromagnetic state with a Curie temperature of T Curie ≈ 190 K and a large low-temperature saturation moment of about 3.5 (1) μ B. These results suggest that the LSCO/LCMO superlattices can be used to study the interaction between the antagonistic ferromagnetic and superconducting orders and, in combination with previous studies on YBCO/LCMO superlattices, may allow one to identify the relevant mechanisms.« less
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