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We report a detailed analysis of the electrical resistivity exponent of thin films of NdNiO3 as a function of epitaxial strain. Thin films under low strain conditions show a linear dependence of the resistivity versus temperature, consistent with a classical Fermi gas ruled by electron-phonon interactions. In addition, the apparent temperature exponent, n, can be tuned with the epitaxial strain between n = 1 and n = 3. We discuss the critical role played by quenched random disorder in the value of n. Our work shows that the assignment of Fermi/Non-Fermi liquid behaviour based on experimentally obtained resistivity exponents requires an in-depth analysis of the degree of disorder in the material. ; Qikai Guo and Saeedeh Farokhipoor acknowledge financial support from a China Scholarship Council (CSC) grant and a VENI grant (016.veni.179.053) of the Netherlands Organisation for Scientific Research (NWO), respectively. Francisco Rivadulla acknowledges support by the Ministry of Science of Spain (Project No. MAT2016-80762-R), the Conselleria de Cultura, Educacion e Ordenacion Universitaria. Xunta de Galicia (ED431F 2016/008, and Centro singular de investigación de Galicia accreditation 2016–2019, ED431G/09), the European Union (European Regional Development Fund (ERDF)) and the European Commission through the project 734187- SPI-COLOST (H2020-MSCA-RISE-2016). ; Peer reviewed

This article belongs to the Special Issue Advances in Magnetic Force Microscopy. ; The fabrication of nanostructures with high resolution and precise control of the deposition site makes Focused Electron Beam Induced Deposition (FEBID) a unique nanolithography process. In the case of magnetic materials, apart from the FEBID potential in standard substrates for multiple applications in data storage and logic, the use of this technology for the growth of nanomagnets on different types of scanning probes opens new paths in magnetic sensing, becoming a benchmark for magnetic functionalization. This work reviews the recent advances in the integration of FEBID magnetic nanostructures onto cantilevers to produce advanced magnetic sensing devices with unprecedented performance. ; This research was funded by the Spanish Ministry of Economy and Competitiveness through the projects PID2020-112914RB-100, MAT2017-82970-C2-1-R, MAT2017-82970-C2-2-R and MAT2018-102627-T, BES-2015-072950, the Aragon Regional Government (Construyendo Europa desde Aragón) through the project E13_20R with European Social Fund funding. This work has received funding from the European's Union Horizon 2020 research and innovation programme under Grant No. 823717-ESTEEM3. ; Peer reviewed

SrMnO3 has a rich epitaxial strain-dependent ferroic phase diagram, in which a variety of magnetic orderings, even ferroelectricity, and thus multiferroicity, are accessible by gradually modifying the strain. Different relaxation processes, though, including the presence of strain-induced oxygen vacancies, can severely curtail the possibility of stabilizing these ferroic phases. Here, we report on a thorough investigation of the strain relaxation mechanisms in SrMnO3 films grown on several substrates imposing varying degrees of strain from slightly compressive (−0.39%) to largely tensile ≈+3.8%. First, we determine the strain dependency of the critical thickness (tc) below which pseudomorphic growth is obtained. Second, the mechanisms of stress relaxation are elucidated, revealing that misfit dislocations and stacking faults accommodate the strain above tc. Yet, even for films thicker than tc, the atomic monolayers below tc are proved to remain fully coherent. Therefore, multiferroicity may also emerge even in films that appear to be partially relaxed. Last, we demonstrate that fully coherent films with the same thickness present a lower oxygen content for increasing tensile mismatch with the substrate. This behavior proves the coupling between the formation of oxygen vacancies and epitaxial strain, in agreement with first-principles calculations, enabling the strain control of the Mn3+/Mn4+ ratio, which strongly affects the magnetic and electrical properties. However, the presence of oxygen vacancies/Mn3+ cations reduces the effective epitaxial strain in the SrMnO3 films and, thus, the accessibility to the strain-induced multiferroic phase. ; This work was financially supported by the Spanish Ministry of Science through project MAT2017-82970-C2-1-R and MAT2017-82970-C2-2-R and the Aragón Regional Government through projects E13_20R and E28_20R (Construyendo Europa desde Aragón). This project received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no. 823717—ESTEEM3. ; Peer reviewed

We report on the thickness dependence of the ferroelastic domains of PbTiO3 films grown on (110)-DyScO3 with low thicknesses (up to 240 nm), which fall outside the validity range of the square root law proposed by Roytburd. For slow-grown films, the data reveal the linear thickness dependence predicted by Pertsev and Zembilgotov, using a complete elastic description, while a 2/3 scaling exponent is found for fast-grown films. Extremely long domains running all through the samples have been observed in the latter case, compared to the short domains observed in slow-grown films. These differences are ascribed to the in-plane anisotropy for domain wall nucleation, which is likely caused by the anisotropic elastic modulus of the substrate. © 2013 AIP Publishing LLC. ; This work was supported by NanoNextNL, a micro and nanotechnology consortium of the Government of the Netherlands and 130 partners. ; Peer Reviewed

Electron beam induced deposition of 3D cobalt nanowires with simultaneous high metallic content (≈80% at.) and small diameter (<100 nm) has been achieved by optimization of the growth parameters. Two different growth modes have been identified, denoted as radial and linear. In the radial mode, the wire diameter is at least ≈120 nm and the Co content is greater than ≈85% at. In the linear mode, the diameter is smaller than 80 nm and the Co content is at best ≈80% at. A sharp transition between both growth modes can occur inside a single nanowire for certain experimental conditions. Electron holography measurements indicate that in optimized Co nanowires the magnetic induction is high enough for applications in spintronics, magnetic sensing and actuation at the nanoscale. ; This work was supported by the Spanish Ministry of Economy and Competitivity through projects No. MAT2014-51982C2-1-R, MAT2014-51982C2-2-R and MAT2015-69725-REDT, including FEDER funds and by the Aragon Regional Government (Construyendo Europa desde Aragón) through project E26, with FEDER funding. This work was conducted within the framework of the COST Action CM1301 (CELINA). AFP acknowledges funding from a EPSRC Early Career Fellowship EP/M008517/1 and from a Winton Fellowship. In order to comply with EPSRC policy on research data, all metadata associated to this publication can be accessed via https://doi. org/10.17863/CAM.8106. JP-N grant is funded by the Ayuda para Contratos Predoctorales para la Formación de Doctores, Convocatoria Res. 05/06/15 (BOE 12/06/15) of the Secretaría de Estado de Investigación, Desarrollo e Innovación in the Subprograma Estatal de Formación of the Spanish Ministry of Economy and Competitiveness (MINECO) with the participation of the European Social Fund. ; Peer reviewed

This is an open access article published under a Creative Commons Attribution (CC-BY) License.-- et al. ; The investigation of three-dimensional (3D) ferromagnetic nanoscale materials constitutes one of the key research areas of the current magnetism roadmap and carries great potential to impact areas such as data storage, sensing, and biomagnetism. The properties of such nanostructures are closely connected with their 3D magnetic nanostructure, making their determination highly valuable. Up to now, quantitative 3D maps providing both the internal magnetic and electric configuration of the same specimen with high spatial resolution are missing. Here, we demonstrate the quantitative 3D reconstruction of the dominant axial component of the magnetic induction and electrostatic potential within a cobalt nanowire (NW) of 100 nm in diameter with spatial resolution below 10 nm by applying electron holographic tomography. The tomogram was obtained using a dedicated TEM sample holder for acquisition, in combination with advanced alignment and tomographic reconstruction routines. The powerful approach presented here is widely applicable to a broad range of 3D magnetic nanostructures and may trigger the progress of novel spintronic nonplanar nanodevices. ; This work was supported by the European Union under the Seventh Framework Program under a contract for an Integrated Infrastructure Initiative Reference 312483-ESTEEM2. S.B. and A.B. gratefully acknowledge funding by ERC Starting grants number 335078 COLOURATOMS and number 278510 VORTEX. A.F.-P. acknowledges an EPSRC Early Career fellowship and support from the Winton Foundation. E.S., C.G., and L.A.R. acknowledge the French ANR program for support though the project EMMA. J.M.D.T. and C. M. acknowledge the Spanish MINECO projects MAT2014-51982- C2-1-R and MAT2014-51982-C2-2-R, respectively. ; Peer Reviewed

LaNiO3 (LNO) thin films are widely used as electrode materials. Yet, their properties greatly depend on such parameters as strain state and defect density. In this work we present a detailed structural characterization of epitaxial LNO thin films grown on LaAlO3(001). Based on scanning transmission electron microscope - high-angle annular dark-field imaging (STEM-HAADF) contrast analysis and image simulations, Ruddlesden-Popper faulted configurations, with 1/2a relative displacement of defect free perovskite blocks, are atomically modeled and simulated to disentangle the variation of Z-contrast in the experimental images. ; Financial support by the Spanish Government (Projects MAT2013-41506-P, MAT2016-79455-P, and MAT2014- 56063-C2-1-R) and Generalitat de Catalunya (2014-SGR-734 and 2014-SGR-672) is acknowledged. ICMAB-CSIC authors acknowledge financial support from the Spanish Ministry of Economy and Competitiveness, through the "Severo Ochoa" Programme for Centres of Excellence in R&D (SEV- 2015- 0496). ; Peer reviewed

Spin to charge conversion process in a broad range of temperatures is studied in La0.92MnO3/Pt bilayers prepared by polymer-assisted deposition (PAD). It is shown that an excellent LMO/Pt interface can be obtained in spite of using ex situ deposition of the Pt layer. The values obtained for the effective spin-mixing conductance, g↑↓eff = 0.76 × 1015 cm−2, suggest that significant spin transport across the LMO/Pt interface could be achieved. Spin pumping experiments generate a transversal voltage signal VISHE, due to spin to charge conversion via inverse spin Hall effect, that has been detected down to about 100 K with values of the spin-Hall angle, θSH, of about 2.5%, slightly decreasing on reducing temperature in the analyzed temperature range. These results indicate that LMO is a promising perovskite building block for all-oxide multifunctional high-frequency spintronics devices and that PAD technique provides oxide epitaxial thin films of good quality adequate for spintronic applications. ; We acknowledge financial support from the Spanish Ministry of Science, Innovation and Universities through Severo Ochoa (CEX2019-000917-S), and SPINCURIOX (RTI2018-099960-BI00) and AMONANO (PID2020-112914RB-I00) projects co-financed by the European Regional Development Funds. AMONANO also received funding from the European Union's Horizon 2020 research and innovation program under grant agreement no. 823717-ESTEEM3. Hailin Wang acknowledges financial support from the China Scholarship Council (CSC). ; With funding from the Spanish government through the 'Severo Ochoa Centre of Excellence' accreditation (CEX2019-000917-S). ; Peer reviewed

We report the first study on the thermal behavior of the stiffness of individual carbon nanotubes, which is achieved by measuring the resonance frequency of their fundamental mechanical bending modes. We observe a reduction of the Young's modulus over a large temperature range with a slope −(173±65)ppm/K in its relative shift. These findings are reproduced by two different theoretical models based on the thermal dynamics of the lattice. These results reveal how the measured fundamental bending modes depend on the phonons in the nanotube via the Young's modulus. An alternative description based on the coupling between the measured mechanical modes and the phonon thermal bath in the Akhiezer limit is discussed. ; This work is supported by ERC advanced (Grant No. 692876), ERC PoC (Grant No. 862149), Marie Skłodowska-Curie (Grant No. 665884), PROBIST (Grant No. 754510), the Cellex Foundation, the CERCA Programme, AGAUR (Grant No. 2017SGR1664), Severo Ochoa (Grant No. SEV2015-0522), MICINN (Grants No. RTI2018-097953-B-I00 and No. PGC2018-096955-B-C44), the Fondo Europeo de Desarrollo Regional, the Grant No. MAT2017-82970-C2-2-R of Spanish MINECO and the Project No. E13_17R from Aragon Regional Government (Construyendo Europa desde Aragón). F. A. acknowledges support from European Research Council (ERC) starting Grant No. 802093. P. V. acknowledges support from European Research Council (ERC) starting grant 758794 "Q-ROOT." ; Peer reviewed

Understanding the growth mechanisms of nanostructures obtained from chemical solutions, a high-throughput production methodology, is essential to correlate precisely the growth conditions with the nanostructures' morphology, dimensions and orientation. It is shown that self-organized (011)-oriented CeGdO (CGO) nanowires having a single in-plane orientation are achieved when an anisotropic (011)-LaAlO (LAO) substrate is chosen. STEM and AFM images of the epitaxial nanowires reveal the (001)CGO[0-11](011)LAO[100] growth orientation, with the enlargement occurring along the [0-11]CGO direction with (111) lateral facets. The chosen substrate allowed us to study a unique case where the resulting biaxial strain is isotropic, while the dissimilar lateral surface energies are the key factor to obtain an energetically imbalanced and non-degenerated nanowire configuration. Rapid Thermal Annealing (RTA) has allowed sorting of experimental nucleation from coarsening and analysis of the kinetic phenomena of the nanowires. A thermodynamic driving force is shown to exist for a continuous elongation of the nanowires while the coarsening rates are found to be strongly temperature dependent and so kinetic effects are the key factors to control the size and density of the self-organized nanowire system. A remarkably fast nanowire growth rate (14-40 nm min) is observed, which we associate with a high atomic mobility probably linked to a high concentration of oxygen vacancies, as detected by XPS. These nanowires are envisaged as model systems pushing forward the study of low energetic and highly oxygen deficient {111} lateral facets useful for catalysis, gas sensors and ionic conductivity applications. ; We acknowledge financial support from Spanish Ministry of Economy and Competitiveness through the "Severo Ochoa" Programme for Centres of Excellence in R&D (SEV-2013-0295 and SEV-2015-0496), CONSOLIDER Excellence Network (MAT2015-68994-REDC), COACHSUPENERGY project (MAT2014-51778-C2-1-R, co-financed by the European Regional Development Fund), and the projects MAT2011-28874-C02-01, ENE2014-56109-C3-3-R and Consolider Nanoselect (CSD2007-00041), and from the Catalan Government (2014-SGR-753, 2014-SGR-1638 and Xarmae). AQ and MdlM are also grateful for JAE-Predoc fellowship from CSIC (E-08-2012-1321248 and E-08-2013-1028356, co-financed by the European Social Fund). Authors also thank the INA-LMA facilities for the use of the advanced (S)TEM equipment. ; Peer Reviewed

We studied in detail the in-plane magnetic properties of heterostructures based on a ferroelectric BaTiO3 overlayer deposited on a ferromagnetic La2/3Sr1/3MnO3 film grown epitaxially on pseudocubic (001)-oriented SrTiO3, (LaAlO3)0.3(Sr2TaAlO6)0.7 and LaAlO3 substrates. In this configuration, the combination of both functional perovskites constitutes an artificial multiferroic system with potential applications in spintronic devices based on the magnetoelectric effect. La2/3Sr1/3MnO3 single layers and BaTiO3/La2/3Sr1/3MnO3 bilayers using the pulsed-laser deposition technique. We analyzed the films structurally through X-ray reciprocal space maps and high-angle annular dark field microscopy, and magnetically via thermal demagnetization curves and in-plane magnetization versus applied magnetic field loops at room temperature. Our results indicate that the BaTiO3 layer induces an additional strain in the La2/3Sr1/3MnO3 layers close to their common interface. The presence of BaTiO3 on the surface of tensile-strained La2/3Sr1/3MnO3 films transforms the in-plane biaxial magnetic anisotropy present in the single layer into an in-plane uniaxial magnetic anisotropy. Our experimental evidence suggests that this change in the magnetic anisotropy only occurs in tensile-strained La2/3Sr1/3MnO3 film and is favored by an additional strain on the La2/3Sr1/3MnO3 layer promoted by the BaTiO3 film. These findings reveal an additional mechanism that alters the magnetic behavior of the ferromagnetic layer, and consequently, deserves further in-depth research to determine how it can modify the magnetoelectric coupling of this hybrid multiferroic system. ; This work has been supported financially by the "Instituto de Nanociencia de Aragón", Zaragoza, Spain, where the films were partially grown and characterized; Center of Excellence for Novel Materials (CENM); COLCIENCIAS-UNIVALLE research project 110656933104, contract No.2013-0002; UNIVALLE research projects CI 7978 and CI 71109. This work was also supported by the Spanish Ministry of Science (through projects MAT2017-82970-C2-1-R and MAT2017-82970-C2-2-R, including FEDER funding) and the Aragón Regional government (Project No. E26). ; Peer reviewed

(.) Funding by the Spanish Ministry of Science is acknowledged, grants MAT2017-82970-C2-1-R, MAT2017-82970-C2-2-R and MAT2018-102627-T, and by Aragón Government (Construyendo Europa desde Aragón), grant E13_20R including European Social Fund. J.P.-N. acknowledges MINECO funding BES-2015-072950. (.)