Enhancement of the piezoelectric coefficient in PVDF-TrFe/CoFe₂O₄ nanocomposites through DC magnetic poling

• Marco Fortunato,
• Alessio Tamburrano,
• Maria Paola Bracciale,
• Maria Laura Santarelli and
• Maria Sabrina Sarto

Beilstein J. Nanotechnol. 2021, 12, 1262–1270, doi:10.3762/bjnano.12.93

• place between PVDF-TrFe and CoFe2O4 nanoparticles, with the formation of a carbonyl group (C=O), as suggested by the FTIR spectra reported in Figure 1. When the DC magnetic field is applied, the ferromagnetic nanoparticles orient themselves along the direction of the applied field and then drag the

• piezoelectric coefficient by adding ferromagnetic CoFe2O4 nanoparticles to PVDF-TrFe and performing magnetic poling. The highest d33 value, up to 39 pm/V, was obtained after adding 5 wt % of CoFe2O4 nanoparticles and applying a DC magnetic field of 50 mT. Application of the magnetic field produced an alignment

• nanocomposite, including ferromagnetic CoFe2O4 nanoparticles, and the application of a DC magnetic poling provides an alternative route to obtain highly efficient piezoelectric materials with excellent d33 values, avoiding electrical poling or mechanical stretching. This process may be particularly attractive

In situ transport characterization of magnetic states in Nb/Co superconductor/ferromagnet heterostructures

• Olena M. Kapran,
• Roman Morari,
• Taras Golod,
• Evgenii A. Borodianskyi,
• Vladimir Boian,
• Andrei Prepelita,
• Nikolay Klenov,
• Anatoli S. Sidorenko and
• Vladimir M. Krasnov

Beilstein J. Nanotechnol. 2021, 12, 913–923, doi:10.3762/bjnano.12.68

• demonstrate how FORC can be used for detailed in situ characterization of magnetic states. It reveals that upon reduction of the external field, the magnetization in ferromagnetic layers first rotates in a coherent scissor-like manner, then switches abruptly into the antiparallel state and after that splits

• is caused by subtractive (in the AP state) and additive (in the P state) influences of ferromagnetic exchange fields from neighbor F-layers, which are detrimental to the spin-singlet order in S′ [1][2][3][4][5][6][7][8]. Simulations in Figure 1c demonstrate the tunability of superconductivity in such

• MLs. The key technique that we employ for this purpose is FORC, a powerful tool for the characterization of magnetic states in complex ferromagnetic structures [60][61][62]. FORC analysis starts at the same saturated state. Then the field is swept to a reversal field Hr and measurements are carried

Comprehensive review on ultrasound-responsive theranostic nanomaterials: mechanisms, structures and medical applications

• Sepand Tehrani Fateh,
• Lida Moradi,
• Elmira Kohan,
• Michael R. Hamblin and
• Amin Shiralizadeh Dezfuli

Beilstein J. Nanotechnol. 2021, 12, 808–862, doi:10.3762/bjnano.12.64

Recent progress in actuation technologies of micro/nanorobots

• Ke Xu and
• Bing Liu

Beilstein J. Nanotechnol. 2021, 12, 756–765, doi:10.3762/bjnano.12.59

• content about MC-1 magnetotactic bacteria (MTB) in the treatment of cancer, especially as a supplementary means to advance in smaller capillaries. Therefore, Martel innovatively used MC-1 magnetotactic bacteria combined with ferromagnetic materials to push microbeads and therapeutic agents together for

Recent progress in magnetic applications for micro- and nanorobots

• Ke Xu,
• Shuang Xu and
• Fanan Wei

Beilstein J. Nanotechnol. 2021, 12, 744–755, doi:10.3762/bjnano.12.58

• this article, recent progress in magnetic applications in the field of micro- and nanorobots is reviewed. First, the achievements of manufacturing micro- and nanorobots by incorporating different magnetic nanoparticles, such as diamagnetic, paramagnetic, and ferromagnetic materials, are discussed in

• transportation of cargo [22][23], and transmit energy. Compared with other concepts, magnetic MNRs that combine diamagnetic, paramagnetic, and ferromagnetic materials [24] could have a greater driving force and exhibit characteristics such as biocompatibility [25]. Hence, magnetic nanoparticles (MNPs) are widely

• according to the alignment and response of magnetic dipoles, magnetic materials can be divided into diamagnetic, paramagnetic [31], ferromagnetic, ferrimagnetic, and antiferromagnetic. Diamagnetism of the material can be attributed to the orbital angular momentum, which is a phenomenon in which

A review of defect engineering, ion implantation, and nanofabrication using the helium ion microscope

• Frances I. Allen

Beilstein J. Nanotechnol. 2021, 12, 633–664, doi:10.3762/bjnano.12.52

• junctions by the HIM method has again been demonstrated [48]. Ferromagnetic properties The first demonstration of defect engineering using the HIM was actually for a magnetic device by Franken and co-authors [49]. In this work, ferromagnetic microstrips comprising Pt(4 nm)/Co(0.6 nm)/Pt(2 nm) layers on an

• demonstrated [51]. Furthermore, tuning of the metamagnetic transition temperature of an FeRh thin film (from antiferromagnetic to ferromagnetic behavior) has been achieved by varying the helium ion dose from 1 × 1014 to 5 × 1015 ions/cm2, with the patterning of features down to 25 nm in size [52]. In a study

• the collision cascade to create individual ferromagnetic domains in a previously non-ferromagnetic material [55]. In the cited work, Röder et al. used this phenomenon of disorder-induced ferromagnetism, together with the small probe size of the neon ion beam, to directly write nanomagnets into a

Spontaneous shape transition of Mn_xGe_1−x islands to long nanowires

• S. Javad Rezvani,
• Luc Favre,
• Gabriele Giuli,
• Yiming Wubulikasimu,
• Isabelle Berbezier,
• Augusto Marcelli,
• Luca Boarino and
• Nicola Pinto

Beilstein J. Nanotechnol. 2021, 12, 366–374, doi:10.3762/bjnano.12.30

• literature for other heteroepitaxial systems. Our study gives experimental evidence for the spontaneous formation of spatially uniform and compositionally homogeneous Mn-rich GeMn nanowires on Ge(111). The reliable and simple synthesis approach allows one to exploit the room-temperature ferromagnetic

• ]. The growth of MnxGe1−x alloys on Ge wafers, and in particular of Mn5Ge3, has been studied extensively in recent years [18][19][20][21][22][23][24]. The high Curie temperature of Mn5Ge3 (≈296 K), in particular, can make it suitable to exploit ferromagnetic properties in everyday applications [25][26

• ≃1.5 μm in length. Considering that several Mn-rich Ge–Mn phases are usually ferromagnetic at room temperature, our results offer an alternative route to a simple and fast fabrication process of novel nanodevices, capable to exploit ferromagnetic properties. SEM images of the morphological evolution of

Nickel nanoparticle-decorated reduced graphene oxide/WO₃ nanocomposite – a promising candidate for gas sensing

• Ilka Simon,
• Alexandr Savitsky,
• Rolf Mülhaupt,
• Vladimir Pankov and
• Christoph Janiak

Beilstein J. Nanotechnol. 2021, 12, 343–353, doi:10.3762/bjnano.12.28

• with a noncollinear spin configuration, which causes the formation of a surface spin canting due to thermal fluctuation of magnetic moments. Figure 7 shows the temperature dependence of the magnetization obtained in the course of the last measurement cycle at which, for nickel particles, ferromagnetic

Exploring the fabrication and transfer mechanism of metallic nanostructures on carbon nanomembranes via focused electron beam induced processing

• Christian Preischl,
• Linh Hoang Le,
• Elif Bilgilisoy,
• Armin Gölzhäuser and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2021, 12, 319–329, doi:10.3762/bjnano.12.26

• irradiation (100 eV, 120 mC/cm2) the whole surface of the cross-linked SAM is afterwards covered with clean iron nanocrystals (Figure S6d,e in Supporting Information File 1). The insulating ultrathin CNM is covered with a thin layer of conductive ferromagnetic iron crystals. By this process laterally

The patterning toolbox FIB-o-mat: Exploiting the full potential of focused helium ions for nanofabrication

• Victor Deinhart,
• Lisa-Marie Kern,
• Jan N. Kirchhof,
• Sabrina Juergensen,
• Joris Sturm,
• Enno Krauss,
• Thorsten Feichtner,
• Sviatoslav Kovalchuk,
• Michael Schneider,
• Dieter Engel,
• Bastian Pfau,
• Bert Hecht,
• Kirill I. Bolotin,
• Stephanie Reich and
• Katja Höflich

Beilstein J. Nanotechnol. 2021, 12, 304–318, doi:10.3762/bjnano.12.25

• , atomic composition, and crystallographic phase [33][34]. Here, the impact of He irradiation on the ferromagnetic multilayer [Co0.6/Pt0.8]15 is studied [35][36]. This multilayer shows perpendicular magnetic anisotropy arising from the Co/Pt interfaces and forms nanometer-scale, labyrinth-like domains with

Nanocasting synthesis of BiFeO₃ nanoparticles with enhanced visible-light photocatalytic activity

• Thomas Cadenbach,
• Maria J. Benitez,
• A. Lucia Morales,
• Cesar Costa Vera,
• Luis Lascano,
• Francisco Quiroz,
• Alexis Debut and
• Karla Vizuete

Beilstein J. Nanotechnol. 2020, 11, 1822–1833, doi:10.3762/bjnano.11.164

• visible-light region (2.1–2.8 eV), high chemical stability, and ferroelectric and ferromagnetic properties at room temperature [19][20][21][22][23][24][25][26][27]. Furthermore, slow electron–hole recombination as a result of efficient separation of the charge carriers has yielded an enhancement of its

Molecular dynamics modeling of the influence forming process parameters on the structure and morphology of a superconducting spin valve

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Vladimir Boian,
• Roman Morari and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1776–1788, doi:10.3762/bjnano.11.160

• This work is a study of the formation processes and the effect of related process parameters of multilayer nanosystems and devices for spintronics. The model system is a superconducting spin valve, which is a multilayer structure consisting of ferromagnetic cobalt nanolayers separated by niobium

• atomic structures depending on the main parameters of the deposition process. Keywords: hybrid nanostructure; mathematical modeling; modified embedded-atom method; molecular dynamics; spintronics; spin valve; vacuum deposition; Introduction Multilayer superconductor/ferromagnetic (S/F) hybrid

• ferromagnetic layers causes a restructuring of the magnetic moment configuration under low-power magnetic fields and switches the spin valve from a high to a low resistance state. When a superconducting film is used as a magneto-resistive interlayer, a superconducting spin valve is obtained. Furthermore, these

Functional nanostructures for electronics, spintronics and sensors

• Anatolie S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1704–1706, doi:10.3762/bjnano.11.152

• functional nanostructures consisting of alternating layers of ferromagnetic and superconducting materials – has been observed. Due to the proximity effect of superconductor/ferromagnetic (S/F) layers and Andreev reflection of Cooper pairs at the S/F interface, a number of new phenomena were first

• in astrophysics and read-out tracts measuring signals generated by quantum circuits at a frequency of 6–9 GHz. Summarizing the above-mentioned milestones, one can see that the main focus of this thematic issue is the new area of research: superconductor/ferromagnetic hybrid nanostructures and their

Antimicrobial metal-based nanoparticles: a review on their synthesis, types and antimicrobial action

• Matías Guerrero Correa,
• Fernanda B. Martínez,
• Cristian Patiño Vidal,
• Camilo Streitt,
• Juan Escrig and
• Carol Lopez de Dicastillo

Beilstein J. Nanotechnol. 2020, 11, 1450–1469, doi:10.3762/bjnano.11.129

• , size and magnetic nature enables them to kill microorganisms through the application of an external magnetic field, resulting in an increase of the therapeutic antimicrobial properties, especially when compared to conventional antimicrobial compounds [136]. Ferromagnetic nanoparticles are probably the

• -volume ratio, increasing the surface of the atoms [19]. In addition, when a magnetic field is applied the magnetic moments of these ferromagnetic FeO NPs become aligned. The surface of the SPIONs can be modified to specifically improve their functionality as antimicrobial compounds by increasing their

Controlling the proximity effect in a Co/Nb multilayer: the properties of electronic transport

• Sergey Bakurskiy,
• Mikhail Kupriyanov,
• Nikolay V. Klenov,
• Igor Soloviev,
• Andrey Schegolev,
• Roman Morari,
• Yury Khaydukov and
• Anatoli S. Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1336–1345, doi:10.3762/bjnano.11.118

• We present both theoretical and experimental investigations of the proximity effect in a stack-like superconductor/ferromagnetic (S/F) superlattice, where ferromagnetic layers with different thicknesses and coercive fields are made of Co. Calculations based on the Usadel equations allow us to find

• superlattices can be used as tunable kinetic inductors designed for artificial neural networks representing the information in a “current domain”. Keywords: cryogenic computing; spin-valve; superconducting neural network; superconducting spintronics; Introduction Multilayer superconductor/ferromagnetic (S/F

• ferromagnetic (F) layers separated by thin superconducting layers, in which the superconducting order parameter is maintained due to the proximity to a thick superconducting bank (S-bank). Switching from the antiparallel (AP) to the parallel (P) alignment of neighboring F1 and F2 layers leads to a significant

Proximity effect in [Nb(1.5 nm)/Fe(x)]₁₀/Nb(50 nm) superconductor/ferromagnet heterostructures

• Yury Khaydukov,
• Sabine Pütter,
• Laura Guasco,
• Roman Morari,
• Gideok Kim,
• Thomas Keller,
• Anatolie Sidorenko and
• Bernhard Keimer

Beilstein J. Nanotechnol. 2020, 11, 1254–1263, doi:10.3762/bjnano.11.109

• ferromagnetic properties. The proximity of this weak ferromagnetic layer to a thick superconductor leads to an intermediate phase that is characterized by a suppressed but still finite resistance of structure in a temperature interval of about 1 K below the superconducting transition of thick Nb. By increasing

Applications of superparamagnetic iron oxide nanoparticles in drug and therapeutic delivery, and biotechnological advancements

• Maria Suciu,
• Corina M. Ionescu,
• Alexandra Ciorita,
• Septimiu C. Tripon,
• Dragos Nica,
• Hani Al-Salami and
• Lucian Barbu-Tudoran

Beilstein J. Nanotechnol. 2020, 11, 1092–1109, doi:10.3762/bjnano.11.94

• SPIONs smaller than 10 nm, by Néel and Brownian relaxation for SPIONs between 10 and 13 nm (mechanisms in superparamagnetic nanoparticles), and by hysteresis loss for larger SPIONs (mechanism of ferromagnetic nanoparticles) [139]. Hyperthermia potential and efficacy of SPIONs depend on their structure

• studies referring to the dimensions of single domains for iron oxides. Up to 25 nm magnetite exhibits superparamagnetic behavior and around 80 nm it exhibits ferromagnetic behavior. Maghemite is superparamagnetic up to 35 nm and ferromagnetic up to 90 nm [140]. The ideal nanoparticle for hyperthermia has

Wet-spinning of magneto-responsive helical chitosan microfibers

• Dorothea Brüggemann,
• Johanna Michel,
• Naiana Suter,
• Matheus Grande de Aguiar and
• Michael Maas

Beilstein J. Nanotechnol. 2020, 11, 991–999, doi:10.3762/bjnano.11.83

• nanoparticles agglomerated into clusters inside the fiber matrix. The helical constructs exhibited a diameter of approximately 500 µm with one to two windings per millimeter. Due to their ferromagnetic properties they are easily attracted to a permanent magnet. The results from the tensile testing show that the

• [39]. Since the magnetic particles used in this work were approximately 100 nm in diameter, the wet-spun chitosan fibers obtained were clearly ferromagnetic rather than superparamagnetic [40]. This observation was confirmed by the magnetic hysteresis curves which showed a maximum remanent

• , resulting in strong ferromagnetic properties of the fibers. Since the generated fibers had magnetic properties they could be attracted to and stretched by a permanent magnet. The dried chitosan helices had a spring-like elastic behavior. The composite fibers exhibited a Young’s modulus of approximately 14

Epitaxial growth and superconducting properties of thin-film PdFe/VN and VN/PdFe bilayers on MgO(001) substrates

• Wael M. Mohammed,
• Igor V. Yanilkin,
• Amir I. Gumarov,
• Airat G. Kiiamov,
• Roman V. Yusupov and
• Lenar R. Tagirov

Beilstein J. Nanotechnol. 2020, 11, 807–813, doi:10.3762/bjnano.11.65

• choice for superconducting MRAM materials, in which vanadium nitride (VN) serves as the superconductor. The magnetic anisotropies of a 20 nm thick Pd0.96Fe0.04 film of the first-generation epitaxial sample of VN/Pd0.96Fe0.04 on MgO(001) were studied by using a ferromagnetic resonance technique in [34

• allowing to see only the proximity effect of the ferromagnetic layer on the properties of the superconducting VN layer, the latter was deposited in one run for all studied samples. To do this, we mounted two 10 × 5 × 0.5 mm3 MgO substrates close and parallel to each other on the sample holder and used a

• . Magnetic moment measurements shown in Figure 4 confirm the composition of Pd0.96Fe0.04 and Pd0.92Fe0.08 through the ferromagnetic transition temperature TC ≈ 125 K and TC ≈ 240 K, respectively [41]. Temperature dependence of resistance and superconducting transition A physical property measurement system

Observation of unexpected uniaxial magnetic anisotropy in La_2/3Sr_1/3MnO₃ films by a BaTiO₃ overlayer in an artificial multiferroic bilayer

• John E. Ordóñez,
• Lorena Marín,
• Luis A. Rodríguez,
• Pedro A. Algarabel,
• José A. Pardo,
• Roger Guzmán,
• Luis Morellón,
• César Magén,
• Etienne Snoeck,
• María E. Gómez and
• Manuel R. Ibarra

Beilstein J. Nanotechnol. 2020, 11, 651–661, doi:10.3762/bjnano.11.51

• , Universidad de Zaragoza, 50018 Zaragoza, Spain 10.3762/bjnano.11.51 Abstract 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

• 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. Keywords: artificial multiferroic system; BaTiO3; interface-induced strain; La2/3Sr1/3MnO3

• ., ferromagnetic (FM) for LSMO and ferroelectric (FE) for BTO, and BTO/LSMO heterostructures have exhibited magnetoelectric coupling (MEC) [6][7][8]. They constitute a type of artificial hybrid multiferroic material that can be employed to build the next-generation sensors, multiple-state memory elements, magnetic

Multilayer capsules made of weak polyelectrolytes: a review on the preparation, functionalization and applications in drug delivery

• Varsha Sharma and
• Anandhakumar Sundaramurthy

Beilstein J. Nanotechnol. 2020, 11, 508–532, doi:10.3762/bjnano.11.41

Anomalous current–voltage characteristics of SFIFS Josephson junctions with weak ferromagnetic interlayers

• Tairzhan Karabassov,
• Anastasia V. Guravova,
• Aleksei Yu. Kuzin,
• Elena A. Kazakova,
• Shiro Kawabata,
• Boris G. Lvov and
• Andrey S. Vasenko

Beilstein J. Nanotechnol. 2020, 11, 252–262, doi:10.3762/bjnano.11.19

• Physical Institute, Russian Academy of Sciences, 119991 Moscow, Russia 10.3762/bjnano.11.19 Abstract We present a quantitative study of the current–voltage characteristics (CVC) of SFIFS Josephson junctions (S = bulk superconductor, F = metallic ferromagnet, I = insulating barrier) with weak ferromagnetic

• method. Then we obtain the CVC of corresponding SFIFS junctions, and discuss their properties for different set of parameters including the thicknesses of ferromagnetic layers, the exchange field, and the magnetic scattering time. We observe an anomalous nonmonotonic CVC in case of weak ferromagnetic

• superconductivity and ferromagnetism are two competing antagonistic orders. In superconductors (S) electrons form Cooper pairs with opposite spins and momenta, while in ferromagnetic metals (F) electron spins tend to align in parallel. Nevertheless, it is possible to combine S and F layers in one hybrid structure

Nonequilibrium Kondo effect in a graphene-coupled quantum dot in the presence of a magnetic field

• Levente Máthé and
• Ioan Grosu

Beilstein J. Nanotechnol. 2020, 11, 225–239, doi:10.3762/bjnano.11.17

• be realized by a molecular junction or a single quantum dot (QD) or many QDs in a particular arrangement coupled to charge reservoirs by metallic [10][11][12][13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28][29][30][31], ferromagnetic [32][33][34][35] or graphene electrodes [36][37][38

Targeted therapeutic effect against the breast cancer cell line MCF-7 with a CuFe₂O₄/silica/cisplatin nanocomposite formulation

• B. Rabindran Jermy,
• Vijaya Ravinayagam,
• Widyan A. Alamoudi,
• Dana Almohazey,
• Hatim Dafalla,
• Lina Hussain Allehaibi,
• Abdulhadi Baykal,
• Muhammet S. Toprak and
• Thirunavukkarasu Somanathan

Beilstein J. Nanotechnol. 2019, 10, 2217–2228, doi:10.3762/bjnano.10.214

• presence of small-sized nanoclusters at the walls of hexagonal-shaped MCM-41 tends to form superparamagnetic interactions among Fe3+ species, while large nanoclusters contribute to ferromagnetic properties [17]. In our study, paramagnetic behavior with narrow hysteresis demonstrates the formation of small

Nitrogen-vacancy centers in diamond for nanoscale magnetic resonance imaging applications

• Alberto Boretti,
• Lorenzo Rosa,
• Jonathan Blackledge and
• Stefania Castelletto

Beilstein J. Nanotechnol. 2019, 10, 2128–2151, doi:10.3762/bjnano.10.207

• , while producing deep tissue imaging with outstanding contrast, enabling anatomical and functional observation at the same time. Contrast agents are chemical substances used to enhance and improve the quality of the MRI images. The ferromagnetic or paramagnetic nature of a contrast agent determines the

• NV centers and employed to image thin ferromagnetic films. The accuracy obtained is sub-micrometer over surfaces as wide as 100 × 100 µm2 and the imaging speed is fast enough to obtain a real-time video of the evolution of stray magnetic patterns. It is not necessary to supply a microwave signal to

• allows imaging of metal spins via the Hall effect [55]. NV center wide-field microscopy was applied in [11] to characterize and image magnetic samples; sample thin ferromagnetic films were used to map and image their sub-micrometer stray magnetic field patterns by using an array of NV center spins. Using