Magnetic Materials, Thin Films and Nanostructures (Volume II)

A special issue of Magnetochemistry (ISSN 2312-7481). This special issue belongs to the section "Magnetic Materials".

Deadline for manuscript submissions: 31 December 2024 | Viewed by 4976

Special Issue Editors


E-Mail Website
Guest Editor
Faculty of Electrical Engineering Bucharest, National University of Science and Technology Politehnica of Bucharest, 060042 Bucharest, Romania
Interests: magnetic materials; magnetic hysteresis; electromagnetic field computation; planar transformers; power transformers
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

After the success of the first volume of our Special Issue, entitled "Magnetic Materials, Thin Films and Nanostructures", published in May 2023, we cordially invite you to submit your manuscript for consideration and publication in this second volume.

The aim is to cover all relevant aspects of chemical and physical processes in the production and characterization of hard and soft magnetic materials in bulk, thin films, nanostructures and/or nanocomposites, as well as the modeling aspects involving such structures and devices.

Since magnetism plays an important role in the fields of material sciences and electrical engineering, we also welcome relevant manuscripts on engineering and applications with an emphasis on the magnetic behavior of materials and compounds (discussing their properties vs applications, i.e. diamagnetism, paramagnetism, ferromagnetism, ferrimagnetism and antiferromagnetism).

Accordingly, this second volume of the Special Issue welcomes original research and review manuscripts on the challenges and trends covering fundamental and experimental research, with special focus on the design, synthesis and characterization of any type of magnetic material and the study of its structure–property relationships.

We also welcome manuscripts on the development of new experimental concepts, from the transfer, chemical transformation or high-resolution patterning of advanced thin films and nanomaterials, to the design and fabrication of devices.

Dr. Lucian Petrescu
Dr. Catalin Constantinescu
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Magnetochemistry is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2200 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

 

Keywords

  • engineering/processing of magnetic materials
  • nanomaterials/nanostructures and thin films
  • characterization of magnetic materials, nanomaterials/nanostructures and thin films
  • theoretical models and calculations of magnetic materials
  • applications of magnetic materials

Published Papers (3 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

11 pages, 341 KiB  
Article
Doping Effects on the Multiferroic Properties of KNbO3 Nanoparticles
by A. T. Apostolov, I. N. Apostolova and J. M. Wesselinowa
Magnetochemistry 2024, 10(3), 19; https://doi.org/10.3390/magnetochemistry10030019 - 7 Mar 2024
Viewed by 1175
Abstract
The magnetization, polarization, and band-gap energy in pure and ion-doped KNbO3 (KNO) bulk and nanoparticles (NPs) are investigated theoretically using a microscopic model and Green’s function theory. It is shown that KNO NPs are multiferroic. The size dependence of M and P [...] Read more.
The magnetization, polarization, and band-gap energy in pure and ion-doped KNbO3 (KNO) bulk and nanoparticles (NPs) are investigated theoretically using a microscopic model and Green’s function theory. It is shown that KNO NPs are multiferroic. The size dependence of M and P is studied. The magnetization M increases with decreasing NP size, whereas the polarization P decreases slightly. The properties of KNO can be tuned by ion doping, for example, through the substitution of transition metal ions at the Nb site or Na ions at the K site. By ion doping, depending on the relation between the doping and host ion radii, different strains appear. They lead to changes in the exchange interaction constants, which are inversely proportional to the lattice parameters. So, we studied the macroscopic properties on a microscopic level. By doping with transition metal ions (Co, Mn, Cr) at the Nb site, M increases, whereas P decreases. Doped KNO NPs exhibit the same behavior as doped bulk KNO, but the values of the magnetization and polarization in KNO NPs are somewhat enhanced or reduced due to the size effects compared to the doped bulk KNO. In order to increase P, we substituted the K ions with Na ions. The polarization increases with increasing magnetic field, which is evidence of the multiferroic behavior of doped KNO bulk and NPs. The behavior of the band-gap energy Eg also depends on the dopants. Eg decreases with increasing Co, Mn, and Cr ion doping, whereas it increases with Zn doping. The results are compared with existing experimental data, showing good qualitative agreement. Full article
(This article belongs to the Special Issue Magnetic Materials, Thin Films and Nanostructures (Volume II))
Show Figures

Figure 1

13 pages, 3218 KiB  
Article
Magneto-Transport and Enhanced Spin-Polarized Photo Response in Solution-Processed Vertically Aligned Zn0.9Ni0.1O Nanowires
by Jamil Kazmi, Jamal Kazmi, Syed Raza Ali Raza, Babar Nazir, Raja Azhar Saeed Khan, Mohd Ambri Mohamed and Mohsin Rafique
Magnetochemistry 2023, 9(8), 193; https://doi.org/10.3390/magnetochemistry9080193 - 26 Jul 2023
Viewed by 1234
Abstract
In this study, we grew pristine and Ni-doped vertically aligned zinc oxide nanowires (NWs) on a glass substrate. Both the doped and pristine NWs displayed dominant 002 peaks, confirming their vertical alignment. The Ni-doped NWs exhibited a leftward shift compared to the pristine [...] Read more.
In this study, we grew pristine and Ni-doped vertically aligned zinc oxide nanowires (NWs) on a glass substrate. Both the doped and pristine NWs displayed dominant 002 peaks, confirming their vertical alignment. The Ni-doped NWs exhibited a leftward shift compared to the pristine NWs. TEM measurements confirmed the high crystallinity of individual NWs, with a d-spacing of ~0.267 nm along the c-axis. Ni-doped NWs had a higher density, indicating increased nucleation sites due to nickel doping. Doped NW films on glass showed enhanced absorbance in the visible region, suggesting the creation of sub-gap defect levels from nickel doping. Magnetization vs. magnetic field measurements revealed a small hysteresis loop, indicative of soft ferromagnetic behavior. Current transient plots demonstrated an increase in current with an applied magnetic field. Two-terminal devices exhibited a photo response that intensified with magnetic field application. This increase was attributed to parallel grain alignment, resulting in enhanced carrier concentration and photo response. In the dark, transport properties displayed negative magnetoresistance behavior. This magneto-transport effect and enhanced photo response (under an LED at ~395 nm) were attributed to giant magnetoresistance (GMR) in the aligned NWs. The observed behavior arose from reduced carrier scattering, improved transport properties, and parallel spin alignment in the magnetic field. Full article
(This article belongs to the Special Issue Magnetic Materials, Thin Films and Nanostructures (Volume II))
Show Figures

Figure 1

19 pages, 3073 KiB  
Article
Electrically Detected Magnetic Resonance on a Chip (EDMRoC) for Analysis of Thin-Film Silicon Photovoltaics
by Michele Segantini, Gianluca Marcozzi, Denis Djekic, Anh Chu, Daniel Amkreutz, Cham Thi Trinh, Sebastian Neubert, Bernd Stannowski, Kerstin Jacob, Ivo Rudolph, Joseph E. McPeak, Jens Anders, Boris Naydenov and Klaus Lips
Magnetochemistry 2023, 9(7), 183; https://doi.org/10.3390/magnetochemistry9070183 - 15 Jul 2023
Viewed by 1856
Abstract
Electrically detected magnetic resonance (EDMR) is a spectroscopic technique that provides information about the physical properties of materials through the detection of variations in conductivity induced by spin-dependent processes. EDMR has been widely applied to investigate thin-film semiconductor materials in which the presence [...] Read more.
Electrically detected magnetic resonance (EDMR) is a spectroscopic technique that provides information about the physical properties of materials through the detection of variations in conductivity induced by spin-dependent processes. EDMR has been widely applied to investigate thin-film semiconductor materials in which the presence of defects can induce the current limiting processes. Conventional EDMR measurements are performed on samples with a special geometry that allows the use of a typical electron paramagnetic resonance (EPR) resonator. For such measurements, it is of utmost importance that the geometry of the sample under assessment does not influence the results of the experiment. Here, we present a single-board EPR spectrometer using a chip-integrated, voltage-controlled oscillator (VCO) array as a planar microwave source, whose geometry optimally matches that of a standard EDMR sample, and which greatly facilitates electrical interfacing to the device under assessment. The probehead combined an ultrasensitive transimpedance amplifier (TIA) with a twelve-coil array, VCO-based, single-board EPR spectrometer to permit EDMR-on-a-Chip (EDMRoC) investigations. EDMRoC measurements were performed at room temperature on a thin-film hydrogenated amorphous silicon (a-Si:H) pin solar cell under dark and forward bias conditions, and the recombination current driven by the a-Si:H dangling bonds (db) was detected. These experiments serve as a proof of concept for a new generation of small and versatile spectrometers that allow in situ and operando EDMR experiments. Full article
(This article belongs to the Special Issue Magnetic Materials, Thin Films and Nanostructures (Volume II))
Show Figures

Figure 1

Back to TopTop