Research

Jump to: Review

13 pages, 3650 KiB

Open AccessArticle

Electrophoretic Deposition of One- and Two-Layer Compacts of Holmium and Yttrium Oxide Nanopowders for Magneto-Optical Ceramics Fabrication

by Elena G. Kalinina, Nataliya D. Kundikova, Dmitrii K. Kuznetsov and Maxim G. Ivanov

Magnetochemistry 2023, 9(11), 227; https://doi.org/10.3390/magnetochemistry9110227 - 15 Nov 2023

Viewed by 1073

Abstract

In this work, the possibility of fabricating composite magneto-optical ceramics by electrophoretic deposition (EPD) of nanopowders and high-temperature vacuum sintering of the compacts was investigated. Holmium oxide was chosen as a magneto-optical material for the study because of its transparency in the mid-IR [...] Read more.

In this work, the possibility of fabricating composite magneto-optical ceramics by electrophoretic deposition (EPD) of nanopowders and high-temperature vacuum sintering of the compacts was investigated. Holmium oxide was chosen as a magneto-optical material for the study because of its transparency in the mid-IR range. Nanopowders of magneto-optical (Ho_0.95La_0.05)₂O₃ (HoLa) material were made by self-propagating high-temperature synthesis. Nanopowders of (Y_0.9La_0.1)₂O₃ (YLa) were made by laser synthesis for an inactive matrix. The process of formation of one- and two-layer compacts by EPD of the nanopowders from alcohol suspensions was studied in detail. Acetylacetone was shown to be a good dispersant to obtain alcohol suspensions of the nanopowders, characterized by high zeta potential values (+29–+80 mV), and to carry out a stable EPD process. One-layer compacts were made from the HoLa and YLa nanopowders with a density of 30–43%. It was found out that the introduction of polyvinyl butyral (PVB) into the suspension leads to a decrease in the mass and thickness of the green bodies deposited, but does not significantly affect their density. The possibility of making two-layer (YLa/HoLa) compacts with a thickness of up to 2.6 mm and a density of up to 46% was demonstrated. Sintering such compacts in a vacuum at a temperature of 1750 °C for 10 h leads to the formation of ceramics with a homogeneous boundary between the YLa/HoLa layers and a thickness of the interdiffused ion layer of about 30 μm. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Graphical abstract

12 pages, 1721 KiB

Open AccessArticle

Magneto-Optical Faraday Effect in Quasicrystalline and Aperiodic Microresonator Structures

by Daria O. Ignatyeva, Polina V. Golovko and Vladimir I. Belotelov

Magnetochemistry 2023, 9(2), 54; https://doi.org/10.3390/magnetochemistry9020054 - 10 Feb 2023

Cited by 1 | Viewed by 1402

Abstract

We theoretically and numerically investigate magnetophotonic microresonators formed by a magnetic layer sandwiched between two reflective multilayers with different layer arrangements. Quasicrystals with the Fibonacci layer sequence and aperiodic structures with the Thue–Morse sequence are all compared to the conventional photonic crystal Bragg [...] Read more.

We theoretically and numerically investigate magnetophotonic microresonators formed by a magnetic layer sandwiched between two reflective multilayers with different layer arrangements. Quasicrystals with the Fibonacci layer sequence and aperiodic structures with the Thue–Morse sequence are all compared to the conventional photonic crystal Bragg microresonators. The magneto-optical spectral properties of such magnetophotonic structures are completely different from each other and from a uniform magnetic film. In multilayered structures of various order types, microresonator modes are excited. The feature of multilayered structures with arrangements different from a periodic one is that they support the excitation of the multiple microresonator modes in a limited visible and near-infrared spectral range. The wavelengths of the two microresonator modes in a regular photonic crystal differ by more than one octave. This feature of the quasi-crystalline and aperiodic microresonators is important for applications in devices based on the Faraday effect. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

13 pages, 6238 KiB

Open AccessFeature PaperEditor’s ChoiceArticle

Fine-Grained Tb₃Al₅O₁₂ Transparent Ceramics Prepared by Co-Precipitation Synthesis and Two-Step Sintering

by Lixuan Zhang, Xiaoying Li, Dianjun Hu, Mariya Dobrotvorska, Roman Yavetskiy, Zhengfa Dai, Tengfei Xie, Qiang Yuan, Haohong Chen, Qiang Liu and Jiang Li

Magnetochemistry 2023, 9(2), 47; https://doi.org/10.3390/magnetochemistry9020047 - 01 Feb 2023

Cited by 4 | Viewed by 1552

Abstract

In recent years, transparent terbium aluminum garnet (TAG) ceramics have attracted much attention for use in high-power Faraday isolators. Fine-grained ceramics usually possess better mechanical properties and accordingly better service performance. In this work, transparent TAG ceramics with fine grains were prepared using [...] Read more.

In recent years, transparent terbium aluminum garnet (TAG) ceramics have attracted much attention for use in high-power Faraday isolators. Fine-grained ceramics usually possess better mechanical properties and accordingly better service performance. In this work, transparent TAG ceramics with fine grains were prepared using a two-step sintering procedure based on the low-temperature sintering process to suppress grain growth. The composition of TAG precursor and powders calcined at different temperatures was studied in detail. The microstructure and relative density of air pre-sintered TAG ceramics were studied to meet the requirements of hot isostatic pressing (HIP) post-treatment. Driven by the low pre-sintering temperature in air, the average grain sizes of the obtained TAG ceramics after HIP treatment are about 2.9–5.3 μm. The TAG ceramics (1.2 mm thick) pre-sintered at 1450 °C with HIP post-treatment at 1550 °C for 3 h under a 176 MPa Ar atmosphere possess the highest in-line transmittance of 80.3% at 1064 nm. The Verdet constant of the TAG ceramics at 632.8 nm is −180.5 rad·T⁻¹·m⁻¹ at room temperature, which is about 1.3 times larger than that of the commercial Tb₃Ga₅O₁₂ single crystals. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

11 pages, 2783 KiB

Open AccessArticle

Up-Conversion Luminescence and Magnetic Properties of Multifunctional Er³⁺/Yb³⁺-Doped SiO₂-GdF₃/LiGdF₄ Glass Ceramics

by Corina Secu, Cristina Bartha, Cristian Radu and Mihail Secu

Magnetochemistry 2023, 9(1), 11; https://doi.org/10.3390/magnetochemistry9010011 - 29 Dec 2022

Viewed by 1716

Abstract

Glassy nanocomposites containing Yb³⁺/Er³⁺-doped GdF₃ and LiGdF₄ nanocrystals have been prepared by controlled crystallization of the xerogel and the structural, up-conversion luminescence, and magnetic properties were analyzed and discussed. Structural and morphological analysis showed uniform distribution of [...] Read more.

Glassy nanocomposites containing Yb³⁺/Er³⁺-doped GdF₃ and LiGdF₄ nanocrystals have been prepared by controlled crystallization of the xerogel and the structural, up-conversion luminescence, and magnetic properties were analyzed and discussed. Structural and morphological analysis showed uniform distribution of both GdF₃ and LiGdF₄ nanocrystals (tens of nm size), embedded in silica glass matrix as the result of thermal decomposition of the trifluoracetates, revealed as a strong exothermic peak at about 300 °C; the Li-ions co-doping showed a strong influence on the GdF₃ and LiGdF₄ nanocrystalline fraction. The energy dispersive spectrometry mapping showed Gd, F and Yb, Er within the nanocrystals but not in the silica glass matrix. X-ray diffraction pattern analysis indicated the crystalline lattice distortion consistent with the Yb/Er incorporation in both fluoride nanocrystals. The “green” ((²H_11/2, ⁴S_3/2) →⁴I_15/2) and “red” (⁴F_9/2→⁴I_15/2) up-conversion luminescences at 525, 545, and 660 nm observed under 980 nm laser light pumping were assigned to the Er³⁺ ions deexcitation through a two-photon process. The magnetic properties of the nanocomposite are strongly temperature dependent. The magnetization hysteresis loops show a ferromagnetic behavior at low temperatures (5K) related to the rare-earth ions contribution and the saturation magnetization of 39 emu/g. At 300 K a paramagnetic behavior was observed that was ascribed to the non-interacting localized nature of the magnetic moment of the rare-earth ions. Hence, such novel, multifunctional magnetic and optical materials can allow the intertwining between magnetism and photonics and might offer new opportunities for new magneto-optical device development. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

9 pages, 6488 KiB

Open AccessArticle

Effect of ZrO₂ Content on Microstructure Evolution and Sintering Properties of (Tb_0.7Lu_0.3)₂O₃ Magneto-Optic Transparent Ceramics

by Yu Xin, Tao Xu, Yaozhi Wang, Peng Luo, Weiwei Li, Bin Kang, Bingchu Mei and Wei Jing

Magnetochemistry 2022, 8(12), 175; https://doi.org/10.3390/magnetochemistry8120175 - 01 Dec 2022

Cited by 3 | Viewed by 1263

Abstract

In this paper, (Tb_0.7Lu_0.3)₂O₃ magneto-optical transparent ceramics with different ZrO₂ doping levels (0~5 at%) were prepared by hydrogen sintering and sequential HIP technique using ZrO₂ as a sintering aid. The effect of ZrO₂ [...] Read more.

In this paper, (Tb_0.7Lu_0.3)₂O₃ magneto-optical transparent ceramics with different ZrO₂ doping levels (0~5 at%) were prepared by hydrogen sintering and sequential HIP technique using ZrO₂ as a sintering aid. The effect of ZrO₂ doping content on the microstructure and optical properties of (Tb_0.7Lu_0.3)₂O₃ ceramics was analyzed. We found that the optimal doping content of ZrO₂ was 3 at%. The transmittance of 3 at% ZrO₂-doped (Tb_0.7Lu_0.3)₂O₃ ceramics at the wavelength of 1064 nm was 74.84 %, and the Verdet constant was approximately 275.28 rad·T⁻¹·m⁻¹ at the wavelength of 650 nm. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

13 pages, 3909 KiB

Open AccessArticle

Terbium (III) Oxide (Tb₂O₃) Transparent Ceramics by Two-Step Sintering from Precipitated Powder

by Dianjun Hu, Xiaoying Li, Lixuan Zhang, Ilya Snetkov, Penghui Chen, Zhengfa Dai, Stanislav Balabanov, Oleg Palashov and Jiang Li

Magnetochemistry 2022, 8(7), 73; https://doi.org/10.3390/magnetochemistry8070073 - 12 Jul 2022

Cited by 11 | Viewed by 2322

Abstract

As a result of preliminary air calcination and subsequent reduction in a flowing NH₃ atmosphere of the precursor from the liquid precipitation method for the first time, pure-phase Tb₂O₃ powder with an average particle size of 135 nm was [...] Read more.

As a result of preliminary air calcination and subsequent reduction in a flowing NH₃ atmosphere of the precursor from the liquid precipitation method for the first time, pure-phase Tb₂O₃ powder with an average particle size of 135 nm was prepared. The Tb₂O₃ magneto-optical transparent ceramics with the average grain size of 1.3 μm were successfully fabricated by vacuum pre-sintering and hot isostatic pressing post-treatment from the as-synthesized Tb₂O₃ powder. In-line transmittance values of Tb₂O₃ ceramics reach 70.3% at 633 nm, 78.1% at 1064 nm, and 79.4% at 1400 nm, respectively. Thanks to the high intrinsic concentration of Tb³⁺, Tb₂O₃ ceramics present high Verdet constants of −427.3 and −123.7 rad·T⁻¹·m⁻¹ at 633 and 1064 nm, which are about 3.1 and 3.4 times higher than those of commercial Tb₃Ga₅O₁₂ crystals, respectively. Due to the excellent magneto-optical properties, Tb₂O₃ ceramics are promising candidates for the development of Faraday isolator toward compaction used in visible and near-infrared bands. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

Review

Jump to: Research

12 pages, 1767 KiB

Open AccessFeature PaperEditor’s ChoiceReview

Characteristics and Recent Development of Fluoride Magneto-Optical Crystals

by Zhonghan Zhang, Zhen Wu, Zhen Zhang, Liangbi Su, Anhua Wu, Yang Li and Jianghe Lan

Magnetochemistry 2023, 9(2), 41; https://doi.org/10.3390/magnetochemistry9020041 - 27 Jan 2023

Cited by 7 | Viewed by 1888

Abstract

Magneto-optical materials are the fundamental component of Faraday isolators; therefore, they are significantly important for solid-state laser systems. Fluoride magneto-optical crystals such as CeF₃, KTb₃F₁₀ and LiTbF₄ exhibit advantages of wide transmittance range, high optical homogeneity, smaller [...] Read more.

Magneto-optical materials are the fundamental component of Faraday isolators; therefore, they are significantly important for solid-state laser systems. Fluoride magneto-optical crystals such as CeF₃, KTb₃F₁₀ and LiTbF₄ exhibit advantages of wide transmittance range, high optical homogeneity, smaller thermal lensing and weaker thermal induced depolarization effect, and thus are promising candidates for Faraday isolators in high-power solid-state lasers. Recent progress in crystal growth and characterizations of these fluoride magneto-optical crystals are introduced. Possible applications of Faraday isolators based on various fluoride crystals are discussed, especially for solid-state lasers in the ultraviolet (UV) or infrared (IR) spectral region. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

14 pages, 1067 KiB

Open AccessEditor’s ChoiceReview

Selection of Magneto-Optical Material for a Faraday Isolator Operating in High-Power Laser Radiation

by Ilya Snetkov and Jiang Li

Magnetochemistry 2022, 8(12), 168; https://doi.org/10.3390/magnetochemistry8120168 - 24 Nov 2022

Cited by 5 | Viewed by 1593

Abstract

Faraday isolators are the inherent components of complex laser systems. The isolation degree is essentially determined by the effects that occur in its magneto-optical element, so the choice of material from which it is made is very important. The principal approaches to choosing [...] Read more.

Faraday isolators are the inherent components of complex laser systems. The isolation degree is essentially determined by the effects that occur in its magneto-optical element, so the choice of material from which it is made is very important. The principal approaches to choosing a magneto-optical material for Faraday isolators are addressed. Characteristic features of materials for Faraday devices operating in laser radiation with high average and high peak power are considered. Some trends in magneto-optical ceramics and the advantages and shortcomings of a number of ceramic samples are analyzed. Using the proposed approaches and recommendations will allow to create devices with unique characteristics for any wavelength range for different practical applications. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Figure 1

32 pages, 11573 KiB

Open AccessReview

Magnetic Nanoparticles: An Overview for Biomedical Applications

by Ashi Mittal, Indrajit Roy and Sona Gandhi

Magnetochemistry 2022, 8(9), 107; https://doi.org/10.3390/magnetochemistry8090107 - 17 Sep 2022

Cited by 41 | Viewed by 4666

Abstract

The use of magnetic nanoparticles has greatly expanded for numerous biomedical applications over the past two decades due to their high surface area, size-dependent superparamagnetic properties, precision tunability, and easy surface modification. Magnetic nanoparticles can be engineered and manipulated with other nanoparticles and [...] Read more.

The use of magnetic nanoparticles has greatly expanded for numerous biomedical applications over the past two decades due to their high surface area, size-dependent superparamagnetic properties, precision tunability, and easy surface modification. Magnetic nanoparticles can be engineered and manipulated with other nanoparticles and functional compounds to form multi-modal systems useful in theragnosis. However, superior biocompatibility, high loading efficacy, regulated drug release, and in vitro and in vivo stability are necessary for the efficient incorporation of these nanoparticles into physiological systems. In recent years, considerable advancements have been made and reported both in synthesis and application, given the broad range of biomedical-related prospective uses of magnetic nanoparticles. Here, in this review, we have highlighted some essential works, specifically related to the application of magnetic nanoparticles in drug delivery, magnetic hyperthermia, magnetic resonance imaging, magnetic particle imaging, biosensors, and tissue engineering. Full article

(This article belongs to the Special Issue New Trends in Magneto-Optical Ceramics)

► Show Figures

Graphical abstract

Journal Menu

Journal Browser

New Trends in Magneto-Optical Ceramics

Share This Special Issue

Special Issue Editor

Special Issue Information

Keywords

Published Papers (9 papers)

Research

Review

Further Information

Guidelines

MDPI Initiatives

Follow MDPI