Optimizing electric vehicle powertrains peak performance with robust predictive direct torque control of induction motors: a practical approach and experimental validation.

Enhancing the efficiency of the electric vehicle's powertrain becomes a crucial focus, wherein the control system for the traction motor plays a significant role. This paper presents a novel electric vehicle traction motor control system based on a robust predictive direct torque control approach, an improved version of the conventional DTC, where the traditional switching table and the hysteresis regulators are substituted with a predictive block based on an optimization algorithm. Additionally, a robust predictive speed loop regulator is employed instead of the proportional-integral regulator, which integrates a new cost function with a finite horizon, incorporating integral action into the control law based on a Taylor series expansion. This technique's primary benefit is its independence from the necessity to measure and observe external disturbances, as well as uncertainties related to parameters. The effectiveness of the suggested system was confirmed through simulation and experimental results under the OPAL-RT platform. The findings indicate that the proposed approach outperforms the conventional method in terms of rejecting disturbances, exhibiting robustness to variations in parameters, and minimizing torque ripple.

Comparison of Four Different Dental Implant Removal Techniques in Terms of the Weight and Volume of Bone Loss.

PURPOSE: Several approaches have been suggested for implant removal. However, further research is necessary to review data regarding the amount of bone removed and the duration of removal time for different procedures. This study evaluates and compares various implant removal techniques.  Materials and methods: A polyurethane block was scanned to create an implant surgical guide. Afterward, implant-guided surgery was performed on 60 simulated bone blocks. The implants were then separated into four groups and removed utilizing the counter-torque ratchet, trephine drills, burs, and piezosurgery. RESULTS: For the weight of bone loss, there were significant differences in the median between the counter-torque ratchet technique (CTRT) and trephine (p < 0.01), CTRT and bur (p < 0.01), trephine and piezo (p < 0.01), and bur and piezo (p = 0.04). All groups, except CTRT and the piezo group, demonstrated a statistically significant difference (p < 0.01) in the procedure durations. Regarding the volume of bone loss, a statistically significant difference (p < 0.01) was found between each group.  Conclusions: CTRT showed the least amount of bone loss. On the other hand, the trephine technique was demonstrated to be the fastest. It is essential to consider the limitations and risks when choosing the approach for implant removal.

Progress in Spin Logic Devices Based on Domain-Wall Motion.

Spintronics, utilizing both the charge and spin of electrons, benefits from the nonvolatility, low switching energy, and collective behavior of magnetization. These properties allow the development of magnetoresistive random access memories, with magnetic tunnel junctions (MTJs) playing a central role. Various spin logic concepts are also extensively explored. Among these, spin logic devices based on the motion of magnetic domain walls (DWs) enable the implementation of compact and energy-efficient logic circuits. In these devices, DW motion within a magnetic track enables spin information processing, while MTJs at the input and output serve as electrical writing and reading elements. DW logic holds promise for simplifying logic circuit complexity by performing multiple functions within a single device. Nevertheless, the demonstration of DW logic circuits with electrical writing and reading at the nanoscale is still needed to unveil their practical application potential. In this review, we discuss material advancements for high-speed DW motion, progress in DW logic devices, groundbreaking demonstrations of current-driven DW logic, and its potential for practical applications. Additionally, we discuss alternative approaches for current-free information propagation, along with challenges and prospects for the development of DW logic.

Longitudinal Observation of Micromotion upon Loading of Implant-Abutment Connection.

While technological advances have made implants a good treatment option with a good long-term prognosis, peri-implantitis, which results in alveolar bone resorption around implants, has been observed in some cases. Micromotion at the implant abutment connection can cause peri-implantitis. However, the temporal progression of micromotion upon loading remains unclear. Therefore, we aimed to longitudinally measure micromotion upon loading application on an implant. Implants with Morse-tapered connections were prepared. Custom titanium abutments were fabricated and tightened onto implant bodies at 35 N. A 100 N vertical load was applied for 200,000 cycles. Micromotion was measured when the load was applied, as was the total implant length and removal torque before and after loading. The micromotion was measured from the position data of the jig of the testing machine during loading. The average removal torque was 30.67 N after 10 min of tightening and 27.95 N after loading, indicating a decrease due to loading. The implant length reduced by 3.6 µm under the load. The average micromotion was 0.018 mm at 2 cycles, 0.016 mm at 100,000 cycles, and 0.0157 mm at 200,000 cycles, indicating implant length reduction under the load but not reaching 0. The micromotion between the implant and abutment under a cyclic load decreased over time but did not completely cease. These results highlight the relationship between micromotion and loading, underscoring the importance of careful monitoring and management to mitigate potential complications, such as peri-implantitis, and ensure optimal performance and durability of the implant.

Neuromorphic Computing with Emerging Antiferromagnetic Ordering in Spin-Orbit Torque Devices.

Field-free switching (FFS) and spin-orbit torque (SOT)-based neuromorphic characteristics were realized in a W/Pt/Co/NiO/Pt heterostructure with a perpendicular exchange bias (HEB) for brain-inspired neuromorphic computing (NC). Experimental results using NiO-based SOT devices guided the development of fully spin-based artificial synapses and sigmoidal neurons for implementation in a three-layer artificial neural network. This system achieved impressive accuracies of 91-96% when applied to the Modified National Institute of Standards and Technology (MNIST) image data set and 78.85-81.25% when applied to Fashion MNIST images, due presumably to the emergence of robust NiO antiferromagnetic (AFM) ordering. The emergence of AFM ordering favored the FFS with an enhanced HEB, which suppressed the memristivity and reduced the recognition accuracy. This indicates a trade-off between the requirements for solid-state memory and those required for brain-inspired NC devices. Nonetheless, our findings revealed opportunities by which the two technologies could be aligned via controllable exchange coupling.

Assessment of Torque Teno Virus (TTV) Frequency in Healthy Blood Donors in the Central Region of Iran, Yazd.

Background: Torque teno virus (TTV) is a globally prevalent virus in humans, yet comprehensive knowledge about its prevalence, predominant transmission routes, and pathogenesis remains limited. This study aimed to assess the frequency of TTV infection among healthy blood donors in Yazd, Iran. Materials and Methods: A total of 236 healthy blood donors, devoid of HIV/HBV/HCV infection markers, participated in the study from 2015 to 2016. Nested Polymerase Chain Reaction (PCR) utilizing a set of oligo primers for the 5΄- UTR region was employed to detect TTV DNA in serum samples. Results: The TTV genome was identified in 161 out of 236 (61.2%) healthy blood donors. The mean age for men and women was 43 and 57 years, respectively. Of the participants, 156 were male, and 107 were female. Donor age exhibited a significant association with virus presence (P=0.007); however, gender did not show a statistically significant association with the frequency of TTV infection in healthy blood donors (P=0.3). Conclusion: The study revealed a notably high frequency of the Torque teno virus in Yazd province, aligning with similar findings globally. Further investigations are warranted to elucidate the clinical implications of the virus in the healthy population.

Nano-superhydrophilic and bioactive surface in poor bone environment. Part 1: transition from primary to secondary stability. A controlled clinical trial : Bioactive implant surfaces in poor density bone.

OBJECTIVES: Bioactive surfaces were designed to increase the interaction between the surface and the cells. This may speed up the biological stability and loading protocols. MATERIALS AND METHODS: 36 patients with D3-D4 bone density were recruited and allocated into two groups. 30 bioactive (test group) and 30 traditional (control group) surfaced implants were placed. Insertion torque value (Ncm), insertion torque curve integral (cumulative torque, Ncm), torque density (Ncm/sec), implant stability quotient (ISQ) measured at three timepoints (baseline (T0), 30 (T30) and 45 (T45) days after surgery), and marginal bone loss (MBL) at 6 months of loading were assessed. RESULTS: The mean ISQ and standard deviation at T0, T30, T45 were respectively 74.57 ± 7.85, 74.78 ± 7.31, 74.97 ± 6.34 in test group, and 77.12 ± 5.83, 73.33 ± 6.13, 73.44 ± 7.89 in control group, respectively. Data analysis showed significant differences between groups in ΔISQ at T0-T30 (p = 0.005) and T30-T45 (p = 0.012). Control group showed a significant decrease in ISQ at T30 (p = 0.01) and T45 (p = 0.03) compared to baseline, while no significant change was observed in test group. Due to the stability of the ISQ value ≥ 70, 26 test group and 23 control group implants were functionally loaded after 45 days. Conversely, due to the ISQ < 70 at T45, four test group implants and one control group implant were loaded after 90 days, and 6 control group implants were loaded after 180 days. Neither insertion torque nor ISQ at baseline were correlated with bone density (in Hounsfield units). There was no significant correlation between cumulative torque and ISQ at baseline. There was a significant positive slope in the correlation between torque density and ISQ at baseline, more accentuated in D3 than D4. This correlation remained significant for the test group in D3 bone at day 30 and 45 (p < 0.01 in both time frames), but not in D4 bone, and it was not significant in CG. CONCLUSIONS: The bioactive surface showed better behavior in terms of implant stability in D3-D4 bone quality in the early stages of bone healing. Clinical relevance This study demonstrated that the transition from primary to secondary stability is improved using bioactive surface, especially in cases of poor bone environment (D3/D4 bone).

No-load resistance training as a promising alternative to stop detraining period due to covid-19 lockdown in older adults - Case report.

Restrictions to control the COVID-19 pandemic have caused older adults to stop their usual activities, including physical exercises. The novel approach of isometric no-load resistance training (NLRT) can be an interesting alternative to conventional training to oppose the harmful effects of detraining. We described the design and preliminary evaluation of an eight-week, twice-weekly NLRT program for older adults returning to strength training programs after COVID-19 lockdown. An older woman (66 years, 61.9kg, 158.5cm) and an older man (66 years, 84.1kg, 166.5cm) who were engaged in conventional strength training programs before the first COVID-19 lockdown participated in this case study. We collected muscle thickness measures using a B-mode ultrasound imaging and maximum isometric torque using an isokinetic dynamometer. Our results revealed that NLRT seems to be a good alternative to increase muscle thickness of knee and elbow flexors and extensors muscles in older adults. However, NLRT effects were inconsistent for maximum torque.

Lower limb muscles' thicknesses are weakly associated with dynamic knee valgus during single-leg squat in women with patellofemoral pain.

INTRODUCTION: Patellofemoral pain (PFP) patients often show an altered lower limb alignment during the single-leg squat (SLS). There is evidence that proximal and distal-to-the-knee muscle alterations can modify the lower limb alignment in PFP patients. However, we observed a lack of studies investigating the possible association between the thickness and strength of proximal and distal-to-the-knee muscles and lower limb alignment during SLS in women with PFP. Therefore, this study aimed to investigate the association between the thickness and strength of lower limb muscles and dynamic knee valgus (DKV) during SLS in women with PFP. METHODS: Cross-sectional study, where fifty-five women with PFP were submitted to the following evaluations: (1) muscle thickness (MT) of Gluteus Medius (GMed), Gluteus Maximus (GMax), Vastus Lateralis (VL), and Tibialis Anterior (TA); (2) isometric peak torque of hip abductors, hip external rotators, knee extensors, and foot inversors; and (3) DKV during SLS. RESULTS: There was a significant negative association between GMax's MT and DKV (r = -0.32; p = 0.01), and between TA's MT and DKV (r = -0.28; p = 0.03). No significant correlations were observed between isometric torques and DKV. Regression analysis found that GMax's MT explained 10% of the DKV's variance during SLS. DISCUSSION: Poor lower limb alignment during SLS is weakly associated with proximal and distal-to-the-knee muscle thicknesses, with no association with isometric torque in PFP women. CONCLUSION: Our results suggest that other factors besides strength and muscle thicknesses may explain and improve lower limb alignment in women with PFP.

Immediate effects of kinesiology tape on quadriceps muscle peak torque and knee joint repositioning error in healthy males: Effects of different tensions and directions.

BACKGROUND: Knee joint injuries may result from compromised quadriceps muscle strength or diminished knee joint proprioception. The application of Kinesio tape (KT) on the quadriceps muscle from origin to insertion (OTI-KT) or insertion to origin (ITO-KT) could impact knee joint proprioception and quadriceps muscle strength. This study aims to assess the effects of different tensions and directions of KT application on active and passive knee joint repositioning errors (AJRE and PJRE) and peak concentric and eccentric peak torque (CPT and EPT) of the quadriceps muscles in healthy males. METHOD: Twenty-one healthy males participated in this repeated-measures study design. CPT, EPT, AJRE, and PJRE of the dominant limb were measured by a Biodex dynamometer before and after applying OTI-KT with 0%, 15%, and 40% extra tensions and ITO-KT with 0% tension. RESULTS: ITO-KT demonstrated a significant reduction in AJRE (p < 0.05). Meanwhile, for OTI-KT, a statistically significant difference was observed in both AJRE and PJRE concerning time (F1,126 = 19.74, p < 0.05 for AJRE; F1,126 = 9.96, p < 0.05 for PJRE) and tension (F2,126 = 22.14, p < 0.05 for AJRE; F2,126 = 20.67, p < 0.05 for PJRE). CONCLUSION: Applying KT, especially OTI KT with 40% and 15% extra tension, shows potential in enhancing knee proprioception without immediate impacts on quadriceps muscle torque. This suggests applications in sports performance and knee injury rehabilitation.

Moiré Engineering of Spin-Orbit Torque by Twisted WS2 Homobilayers.

Artificial moiré superlattices created by stacking 2D crystals have emerged as a powerful platform with unprecedented material-engineering capabilities. While moiré superlattices are reported to host a number of novel quantum states, their potential for spintronic applications remains largely unexplored. Here, the effective manipulation of spin-orbit torque (SOT) is demonstrated using moiré superlattices in ferromagnetic devices comprised of twisted WS2/WS2 homobilayer (t-WS2) and CoFe/Pt thin films by altering twisting angle (θ) and gate voltage. Notably, a substantial enhancement of up to 44.5% is observed in SOT conductivity at θ ≈ 8.3°. Furthermore, compared to the WS2 monolayer and untwisted WS2/WS2 bilayers, the moiré superlattices in t-WS2 enable a greater gate-voltage tunability of SOT conductivity. These results are related to the generation of the interfacial moiré magnetic field by the real-space Berry phase in moiré superlattices, which modulates the absorption of the spin-Hall current arising from Pt through the magnetic proximity effect. This study highlights the moiré physics as a new building block for designing enhanced spintronic devices.

Value of different preoperative bone evaluation methods in predicting intraoperative screw insertion torque-a prospective clinical comparative trial.

BACKGROUND CONTEXT: Establishing good screw-bone structural stability is conducive to reducing the risk of postoperative screw loosening. Screw insertion torque is an objective index for evaluating screw-bone structural stability. Therefore, accurate prediction of screw insertion torque can improve the preoperative evaluation of patients, optimize the surgical plan, and improve the surgical effect. At present, the correlation between different bone assessment methods and screw insertion torque is unclear. PURPOSE: The aim of this study was to evaluate the correlation between different bone assessment methods and screw insertion torque and to optimize the predictive performance of screw insertion torque through mathematical modeling combined with different radiology methods. DESIGN: Prospective cross-sectional study. PATIENT SAMPLES: 77 patients with preoperatively available DXA, CT and MRI data who underwent spinal fixation surgeries between October 2022 and September 2023 and 357 sets of screw data were included in this analysis. OUTCOME MEASURES: Spinal, vertebrae-specific and screw trajectory's BMD were measured preoperatively by different imaging modalities. Intraoperative screw insertion torque was measured using an electronic torque wrench. METHODS: Pearson linear correlation, scatter plots and univariate linear regression were used to evaluate the correlation between different bone evaluation methods and screw insertion torque. Different bone evaluation methods were fitted into the prediction model of screw torque and the related equations were obtained. RESULTS: Screw insertion torque had the strongest positive correlation with the volumetric bone mineral density (vBMD) of the screw trajectory (Pedicle screw insertion torque (PSIT): R = 0.618, p<.001; Terminal screw insertion torque (TSIT): R = 0.735, p<.001). A weak negative correlation was found between the screw insertion torque and level specific vertebral bone quality (VBQ) (PSIT: R = -0.178, p=.001; TSIT: R = -0.147, p=.006). We also found that the PSIT was strongly correlated with the TSIT (R = 0.812, p<.001). CONCLUSIONS: Compared to other bone quality assessment methods, screw trajectory vBMD may be better predict the magnitude of screw insertion torque. In addition, we further optimized preoperative assessments by constructing a mathematical model to better predict screw insertion torque. In conclusion, clinicians should select appropriate preoperative bone quality assessment methods, identify potential low-torque patients, optimize surgical plans, and ultimately improve screw insertion accuracy and reduce postoperative screw loosening rate.

Minimum Intensity of Daily Six Eccentric Contractions to Increase Muscle Strength and Size.

Our previous study showed that daily six maximal eccentric contractions that were performed 5 days a week for 4 weeks increased maximal voluntary isometric (MVC-ISO), concentric (MVC-CON), and eccentric contraction (MVC-ECC) strength of the elbow flexors and muscle thickness of biceps brachii and brachialis (MT) by 8.3 ± 4.9%, 11.1 ± 7.4%, 13.5 ± 11.5%, and 10.6 ± 5.1%, respectively. In the present study, we tested the hypothesis that the muscle strength and MT would still increase when the training intensity was reduced to 2/3 or 1/3 of the peak MVC-ECC torque. Thirty-six healthy young (19-24 years) adults who had not performed resistance training were placed to three groups (n = 12/group): 2/3MVC or 1/3MVC that performed six eccentric contractions with 2/3 or 1/3 MVC-ECC load using a dumbbell 5 days a week for 4 weeks or control group that did not perform any training. Changes in the MVC-ISO, MVC-CON, MVC-ECC torque, and MT before and after the 4-week period were compared among the groups and with the group of the previous study in which six maximal eccentric contractions were performed 5 days a week for 4 weeks (MVC group; n = 12). The control and 1/3MVC groups showed no significant changes in any measures. Significant (p < 0.05) increases in MVC-ISO (10.3 ± 11.4%), MVC-CON (10.9 ± 9.5%), and MVC-ECC (9.3 ± 8.8%) torque and MT (10.1 ± 9.2%) were observed for the 2/3MVC group. These changes were not significantly different from those of the MVC group. These results suggest that the 2/3-intensity eccentric contractions with a dumbbell are as effective as maximal-intensity isokinetic eccentric contractions to induce muscle adaptations.

Effect of Weight Distribution and Active Safety Systems on Electric Vehicle Performance.

This paper describes control methods to improve electric vehicle performance in terms of handling, stability and cornering by adjusting the weight distribution and implementing control systems (e.g., wheel slip control, and yaw rate control). The vehicle is first simulated using the bicycle model to capture the dynamics. Then, a study on the effect of weight distribution on the driving behavior is conducted. The study is performed for three different weight configurations. Moreover, a yaw rate controller and a wheel slip controller are designed and implemented to improve the vehicle's performance for cornering and longitudinal motion under the different loading conditions. The simulation through the bicycle model is compared to the experiments conducted on a rear-wheel driven radio-controlled (RC) electric vehicle. The paper shows how the wheel slip controller contributes to the stabilization of the vehicle, how the yaw rate controller reduces understeering, and how the location of the center of gravity (CoG) affects steering behavior. Lastly, an analysis of the combination of control systems for each weight transfer is conducted to determine the configuration with the highest performance regarding acceleration time, braking distance, and steering behavior.

Field-Free Manipulation of Two-Dimensional Ferromagnet CrTe2 by Spin-Orbit Torques.

Electrical manipulation of magnetic states in two-dimensional ferromagnetic systems is crucial in information storage and low-dimensional spintronics. Spin-orbit torque presents a rapid and energy-efficient method for electrical control of the magnetization. In this letter, we demonstrate a wafer-scale spin-orbit torque switching of two-dimensional ferromagnetic states. Using molecular beam epitaxy, we fabricate two-dimensional heterostructures composed of low crystal-symmetry WTe2 and ferromagnet CrTe2 with perpendicular anisotropy. By utilizing out-of-plane spins generated from WTe2, we achieve field-free switching of the CrTe2 perpendicular magnetization. The threshold switching current density in CrTe2/WTe2 is 1.2 × 106 A/cm2, 20 times smaller than that of the CrTe2/Pt control sample even with an external magnetic field. In addition, the switching behavior can be modulated by external magnetic fields and crystal symmetry. Our findings demonstrate a controllable and all-electric manipulation of perpendicular magnetization in a two-dimensional ferromagnet, representing a significant advancement toward the practical implementation of low-dimensional spintronic devices.

Performance analysis and mechanical determinants of the opening lap of the team sprint in elite-level track cycling.

The team sprint (TS) is a three-lap pursuit and the most revered event in track sprint cycling. The opening lap of the TS is an important determinant to the overall performance. But despite it being the most controlled and repeatable task in track sprint cycling, very little data are available to better understand the performance of the opening lap. The aim of this study was split into three-parts: part one, to better understand the profile and the indices thought to be determinants of the opening lap of the TS in elite sprint track cyclists. Part two of the study examined all available timing splits (15, 65, 125 and 250 m) from 36 standing-start laps. Part three of the study examined the peak torque outputs and peak power outputs of different various starts performed over a 3-month period. The results showed time to 125 m exhibited a near perfect relationship with starter lap performance. Very strong relationships were seen with 15 and 65 m split times and final lap performance. Peak torque of the lead starting leg and peak power output were shown to be highly predictive 15 m, 65 and 125 m performance in training. These data suggested the first 15 m is highly important and predicts a disproportionately high level of final opening lap time performance. Therefore, it is likely that peak power output normalised to system mass and peak torque of lead leg is a strong determinant of overall performance in the TS.

Probing structural features in potato starch granules at moderate hydration through the modelling of 1H->13C polarization transfer kinetics.

The structural arrangement of starch polymers in presence of water is known to impact the functional properties of starchy products. In this study, the hydration of potato starch granules was investigated at the molecular level through various 1H->13C polarization transfer solid-state Nuclear Magnetic Resonance (ss-NMR) experiments. The impact of increasing the water content from 12.3 % to 45.9 % was assessed using 13C Cross Polarization Magic Angle Spinning (CPMAS), Variable Contact Time (VCT-CPMAS), Variable Spin Lock (VSL-CPMAS), and T One Rho QUEnching (TORQUE) NMR sequences. Of these, VCT-CPMAS proved to be the most promising. When applied with an optimal number of contact times, it enabled the application of several mathematical models that provided detailed insights into the structuring of protons in the hydrated potato starch granules. At low hydration (12.3 %), the models enabled various structural domains to be distinguished, which we suggest are associated with helical and amorphous structures. At moderate hydration (45.9 %), we tested two fitting models. Two pools of protons were revealed, corresponding to loosely ordered structures on the scale of tens of nanometers. These findings suggest varying water distribution during starch hydration and are likely to indicate variable hydration levels in the multilamellar amorphous structures of starch granules.

Optimal weighting factor design based on entropy technique in finite control set model predictive torque control for electric drive applications.

In the conventional finite control set model predictive torque control, the cost function consists of different control objectives with varying units of measurements. Due to presence of diverse variables in cost function, weighting factors are used to set the relative importance of these objectives. However, selection of these weighting factors in predictive control of electric drives and power converters still remains an open research challenge. Improper selection of weighting factors can lead to deterioration of the controller performance. This work proposes a novel weighting factor tuning method based on the Multi-Criteria-Decision-Making (MCDM) technique called the Entropy method. This technique has several advantages for multi-objective problem optimization. It provides a quantitive approach and incorporates uncertainties and adaptability to assess the relative importance of different criteria or objectives. This technique performs the online tuning of the weighting factor by forming a data set of the control objectives, i.e., electromagnetic torque and stator flux magnitude. After obtaining the error set of control variables, the objective matrix is normalized, and the entropy technique is applied to design the corresponding weights. An experimental setup based on the dSpace dS1104 controller is used to validate the effectiveness of the proposed method for a two-level, three-phase voltage source inverter (2L-3P) fed induction motor drive. The dynamic response of the proposed technique is compared with the previously proposed MCDM-based weighting factor tuning technique and conventional MPTC. The results reveal that the proposed method provides an improved dynamic response of the drive under changing operating conditions with a reduction of 28% in computational burden and 38% in total harmonic distortion, respectively.

Enhanced Spin-Orbit Torque Efficiency in Platinum-Gadolinium Oxide Nanocomposite Films.

Spin-orbit torque (SOT) has emerged as an effective means of manipulating magnetization. However, the current energy efficiency of SOT operation is inefficient due to low damping-like SOT efficiency per unit current bias. In this work, we dope conventional rare earth oxides, GdOy, into highly conductive platinum by magnetron sputtering to form a new group of spin Hall materials. A large damping-like spin-orbit torque (DL-SOT) efficiency of about 0.35 ± 0.013 is obtained in Pt0.70(GdOy)0.30 measured by the spin-torque ferromagnetic resonance (ST-FMR) technique, which is about five times that of pure Pt under the same conditions. The substantial enhancement of the spin Hall effect is revealed by theoretical analysis to be attributed to the strong side jump induced by the rare earth oxide GdOy impurities. Moreover, this large DL-SOT efficiency contributes to a low critical switching current density (8.0 × 106 A·cm-2 in the Pt0.70(GdOy)0.30 layer) in current-induced magnetization switching measurements. This systematic study on SOT switching properties suggests that Pt1-x(GdOy)x is an attractive spin current source with large DL-SOT efficiency for future SOT applications and provides another idea to regulate the spin Hall angle.

Electric field control of spin-orbit torque in annealed Ta/CoFeB/HfOxheterostructures via interfacial oxidation modulation.

Electric field control of spin-orbit torque (SOT) exhibits promising potential in advanced spintronic devices through interfacial modulation. In this work, we investigate the influence of electric field and interfacial oxidation on SOT efficiency in annealed Ta/CoFeB/HfOxheterostructures. By varying annealing temperatures, the damping-like SOT efficiency reaches its peak at the annealing temperature of 320 °C, with an 80% field-free magnetization switching ratio induced by SOT having been demonstrated. This enhancement is ascribed to the annealing-induced modulation of oxygen ion migration at the CoFeB/HfOxinterface. By applying voltages across the Ta/CoFeB/HfOxheterostructures, which drives the O2‒migration across the interface, a reversible, bipolar, and non-volatile modulation of SOT efficiency was observed. The collective influence of annealing temperature and electric field effects on SOT carried out in this work provides an effective approach into facilitating the optimization and control of SOT in spintronic devices.