Annealing and thickness optimisation in CoZrNb and FeSiBNbCu thin films for low-frequency magnetic flux concentrators

Journal of Magnetism and Magnetic Materials · 2025-10-27 · 1 citations

To develop high-performance soft magnetic flux concentrator (MFC) materials, which are crucial for amplifying magnetic fields through the enhancement of local magnetic flux density, two ferromagnetic alloys, (CZN) and (Finemet®), were investigated. Thin films with thicknesses ranging from 100 to 1200 nm were deposited by magnetron sputtering and annealed at various temperatures. CZN demonstrated optimal soft magnetic properties in its as-grown amorphous configuration, requiring no post-deposition treatment. In contrast, annealing significantly improved Finemet’s performance between 200 ° C and 500 ° C , where its nanocrystalline structure yielded ultra-soft behaviour. Additionally, thickness dependence revealed distinct trends in magnetic behaviour for both materials. For CZN, magnetic softness was best achieved at larger thicknesses ( 1200 nm ), while for Finemet, an optimum was observed at intermediate thicknesses ( 800 nm ). Thus, CZN is suited for cases where annealing is impractical, such as CMOS-compatible or MEMS-integrated sensors, as its properties are optimised without further processing, particularly in thicker films. Finemet, however, requires controlled annealing to obtain soft magnetic behaviour, making it suitable for applications that demand maximum permeability and can tolerate higher temperatures. Both materials demonstrate excellent potential for MFC integration in magnetic sensing and spintronic platforms; however, the optimal choice depends on the thermal budget, processing conditions, and the performance metrics prioritised in the target application. • Co 88 Zr 4 Nb 8 (CZN) achieves optimal softness in its as-deposited amorphous state, making it ideal for low-temperature or thermally constrained applications such as CMOS or MEMS integration. • Fe 73.5 Si 15.5 B 7 Nb 3 Cu 1 (Finemet) requires controlled annealing to realize its full potential, demonstrating exceptionally high permeability and ultra-low coercivity in its nanocrystalline phase.

Magnetic Sensing via Oscillation Control in MgO-Based Magnetic Tunnel Junctions

IEEE Transactions on Magnetics · 2025-12-03

We propose an oscillation-controlled magnetic sensing (OCMS) circuit architecture using MgO-based magnetic tunnel junctions (MTJs), and investigate its magnetic field response characteristics. Compared to the conventional sensing-current method commonly used in hard disk drive (HDD) read heads and magnetic sensors, the OCMS approach achieves an output voltage up to 8.1 times higher. Notably, a large oscillation output of 952 mVpp is obtained with sensing current as low as 0.4–0.6 mA flowing through the MTJ. The measured output response shows strong agreement with the TopSpice simulations, which further predict output voltages exceeding 10 Vpp at a sensing current of 0.82 mA and an operation frequency of 10 MHz. These results demonstrate that the OCMS method enables high-output, low-power, and high-frequency magnetic sensing, offering a promising solution for next-generation spintronic sensor technologies.

Manipulating and unveiling contributions of the reactive oxygen species dramatically promote selective photo-oxidation of 5-hydroxymethylfurfural into 2,5-furandicarboxylic acid in aqueous solution

Green Energy & Environment · 2025-07-30 · 1 citations

Achieving high selectivity to 2,5-furandicarboxylic acid (FDCA) in the photocatalytic oxidation of 5-hydroxymethylfurfural (HMF) in aqueous solution advocates the principle of green and sustainable chemistry, but still remains a significant challenge. Herein, manipulating the reactive oxygen species (ROS) has been realized and dramatically promotes the selective photocatalytic oxidation of HMF in aqueous solution. High FDCA yield of 98.6% has been achieved after 3 hours of visible light irradiation over the as-prepared FeO x -Au/TiO 2 catalyst, being one of the leading photocatalytic performances. Furthermore, satisfactory FDCA yields of higher than 80% could be realized even in the outdoor environment under natural sunlight irradiation, regardless of sunny or cloudy weather. A combination study including physical characterization, kinetic analysis, radical trapping experiments and density functional theory calculations unveils the rate-determining step (oxidation of hydroxyl group) and respective contributions of the generated ROS ( 1 O 2 and •O 2 – ) in each step of the entire reaction network. The present work would push ahead the understanding of HMF photocatalytic oxidation and contribute to the rational design of high-performance photocatalysts. This work manipulates and unveils contributions of the reactive oxygen species (ROS) over the as-prepared FeO x -Au/TiO 2 catalyst, achieving high FDCA yield of 98.6% after 3 hours of visible light irradiation. • FDCA yield of 99.8% is achieved in aqueous solution after 3 hours’ irradiation. • Manipulating the ROS dramatically promotes the selectivity to FDCA. • 1 O 2 is the most pivotal ROS for the selective oxidation of HMF. • Oxidation of the hydroxyl group is the rate-determining step. • DFT calculations reveal in-depth understandings about reaction mechanism.

Reductive stress in cancer immunology and targeted therapy

Acta Biochimica et Biophysica Sinica · 2025-09-15 · 3 citations

Reductive stress is characterized by the excessive accumulation of cellular reducing equivalents, leading to the disruption of cellular redox homeostasis and a shift toward a reductive intracellular environment. Immune cells exhibit particularly dynamic redox modulation to adapt to activation and differentiation processes during immune responses, such as tumor recognition and destruction. Unlike their immune counterparts, tumor cells employ a specific metabolic mode for uncontrolled proliferation and survival, which may also lead to a shift in the intracellular redox balance. While extensive research has focused on oxidative stress during the immune response and cancer treatment, studies on reductive stress are still in their infancy. This review summarizes the generation process of reductive stress and its impact on cellular function, detailing its mechanisms in immune cells and various cancers, as well as its relevance to cancer treatment. The aim of this study is to explore new avenues for cancer immunotherapy from the perspective of reductive stress.

Shubnikov–de Haas oscillations in half-metallic ferromagnetic <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi mathvariant="normal">CrO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:math> epitaxial films

Physical review. B./Physical review. B · 2025-05-28 · 1 citations

We present a study of the low-temperature, high-field magnetotransport behavior of epitaxially grown <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:msub><a:mi>CrO</a:mi><a:mn>2</a:mn></a:msub></a:math> thin films on (100) <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"><b:msub><b:mi>TiO</b:mi><b:mn>2</b:mn></b:msub></b:math> substrates. Electron transport measurements confirm high sample quality, with a residual resistivity ratio as large as 45. A logarithmic fit of the low-temperature regime yields a <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"><c:msup><c:mi>T</c:mi><c:mrow><c:mn>4.5</c:mn></c:mrow></c:msup></c:math> power law, indicative of the elusive double-magnon scattering in half-metallic ferromagnets. Angle-dependent anisotropic magnetoresistance (AMR) measurements reveal a large projected density of states along [001] with a maximum AMR value of 2.4%. Pronounced, axis-dependent Shubnikov–de Haas (SdH) oscillations are observed in the longitudinal magnetoresistance (MR), with discrete Landau levels mapped at various tilt angles of the magnetic field. Their angular dependence follows a <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"><d:mrow><d:mn>1</d:mn><d:mo>/</d:mo><d:mo form="prefix">cos</d:mo><d:mi>θ</d:mi></d:mrow></d:math> relation pointing to a highly anisotropic Fermi surface, and amplitude scaling adheres closely to the thermodynamic Lifshitz-Kosevich formalism. The out-of-plane MR reaches 6.58%, the largest reported for <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"><f:msub><f:mi>CrO</f:mi><f:mn>2</f:mn></f:msub></f:math> thin films. Notably, this study presents an observation of SdH oscillations in a half-metallic oxide with near-perfect spin polarization, a significant advancement in the field of spintronics.

Integration of MTJ devices with cryo-CMOS readout circuitry for magnetic field sensing

SSRN Electronic Journal · 2025-01-01

Fatigue behavior of CFRP bars at different stress ratios and long-term sensing stability of embedded FBG sensors

Construction and Building Materials · 2025-12-17

Progress towards integration of MTJ devices with cryo-CMOS readout circuitry for magnetic field sensing

Solid-State Electronics · 2025-12-02 · 1 citations

Tumor treating fields combined with ionizing radiation inhibit the malignant phenotype of lung cancer brain metastasis cells by suppressing DNA damage repair pathways

Brain stimulation · 2025-07-27

BACKGROUND: Brain metastasis (BrM) is a common complication of advanced tumors with poor prognosis. Although radiotherapy remains a key treatment for BrM, it is plagued by issues such as radiation-induced brain necrosis, neurocognitive impairment, and progress post-treatment. Tumor Treating Fields (TTFields) therapy employs medium frequency (100∼300 kHz) and low intensity (1∼3 v/cm) alternating electric fields to inhibit tumors. We explored the effects and mechanisms of TTFields combined with ionizing radiation (IR) on the malignant phenotype of lung cancer brain metastasis (LCBM) cells, with the aim of advancing the clinical adoption of TTFields. METHODS: LCBM cells H1915, PC9-Brm and primary cells were used. The experiments included four groups: Control, 6 Gy, TTFields, and 6 Gy + TTFields group. Cell viability and the number of EDU or Ki67-positive cells, ability of migration and colony formation were assessed; Cell morphology was observed by H&E staining; Bulk transcriptome revealed the potential mechanisms, with the protein levels of differentially expressed genes (DEGs) verified through immunofluorescence assay. DNA damage repair pathways were validated by Western Blot. Additionally, ROS levels, and HO-1 expression were evaluated. RESULTS: The combination of 150 kHz, 2∼2.5 v/cm TTFields and 6 Gy IR effectively suppressed the viability and the number of EDU-positive and Ki67-positive LCBM cells. Following TTFields and IR, the tumor cells exhibited altered morphology and reduced clonogenic and migratory capacities. RNA-seq revealed associations between TTFields combined with IR and various biological processes and mechanisms, including redox reactions (primarily related to mitochondria), DNA replication, transition metal ion transmembrane transport, and heme metabolism. Furthermore, TTFields combined with IR enhanced γH2AX and 53BP1 levels. Increased ROS and HO-1 expression were observed post-treatment. Similarly, LCBM primary cells exhibited decreased Ki67-positive cells along with increased γH2AX and 53BP1 foci following TTFields and IR. TTFields combined with IR exhibited significant suppression on homologous recombination (HR) markers (p-ATM, RAD51), non-homologous end joining (NHEJ) components (DNA-PKcs, KU70, KU80), and microhomology-mediated end joining (MMEJ) effectors (PARP1, p95-NBS1) versus RT alone. CONCLUSIONS: TTFields combined with IR effectively inhibits LCBM cells. Mechanistically, this combined treatment enhanced DNA damage, suppressed DNA damage repair, and elevates ROS levels.

Satellites, core hole excitations, and spin-resolved electronic structure in the spectroscopy of half-metallic <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi>CrO</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>

Physical review. B./Physical review. B · 2025-07-14