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The spin Hall effect (SHE) allows efficient generation of spin polarization or spin current through charge current and plays a crucial role in the development of spintronics. While SHE typically occurs in non-magnetic materials and is time-reversal even, exploring time-reversal-odd (T-odd) SHE, which couples SHE to magnetization in ferromagnetic materials, offers a new charge-spin conversion mechanism with new functionalities. Here, we report the observation of giant T-odd SHE in Fe3GeTe2/MoTe2 van der Waals heterostructure, representing a previously unidentified interfacial magnetic spin Hall effect (interfacial-MSHE). Through rigorous symmetry analysis and theoretical calculations, we attribute the interfacial-MSHE to a symmetry-breaking induced spin current dipole at the vdW interface. Furthermore, we show that this linear effect can be used for implementing multiply-accumulate operations and binary convolutional neural networks with cascaded multi-terminal devices. Our findings uncover an interfacial T-odd charge-spin conversion mechanism with promising potential for energy-efficient in-memory computing. Charge-to-spin conversion allows for the generation and control of spin polarization via a charge current. Typically, this is done with non-magnetic materials with large spin-orbit interactions such as Platinum. Herein, Dai et al demonstrate an intriguing charge-to-spin mechanism, a magnetic spin Hall effect, in a van der Waals heterostructure. [ABSTRACT FROM AUTHOR]

Semiconducting 2D transition metal dichalcogenides (2D TMDs) with tunable electronic properties are a fundamental prerequisite for the development of next generation advanced electronic/optoelectronic devices. However, controllable and quasi‐continuous tuning carrier polarity of monolayered MoS2 ranging from intrinsic n‐type to p‐type via ambipolarity still remains a challenge. Herein, quasi‐continuous tailoring of carrier polarity of monolayered MoS2 through substitutional doping of molybdenum (Mo) with vanadium (V) atoms is presented. Atomic distribution in real space characterized by spherical aberration‐corrected scanning transmission electron microscopy (Cs‐STEM) reveals that the V atoms randomly substitute Mo in monolayered MoS2, and its doping concentration can be tuned in a wide range from 0.7 to ≈10 at.%. Electrical measurements confirm that the carrier polarity of the monolayered MoS2 can be tuned from intrinsic n‐type to p‐type via ambipolarity depending on the V doping degree, consistent with the density functional theory calculations. Moreover, this doping strategy is demonstrated to extend to other monolayered 2D TMDs by using MoSe2 as a model material, owing to a good universality. [ABSTRACT FROM AUTHOR]

3D human trajectory reconstruction in an indoor scene is critical in various applications, such as indoor navigation and human activity recognition. This task is challenging due to occlusion and clutters of indoor scenes, flexible human body joints, and severe lack of relevant datasets. Although several methods have been proposed to reconstruct a 3D human trajectory, they either can recover only 2D positions or require human initiative cooperation. In this paper, we propose a novel framework for 3D human trajectory reconstruction in an indoor scene using monocular surveillance videos and static point clouds without any initiative cooperation. The proposed framework consists of three modules: 3D pose estimation, depth regression, and trajectory reconstruction. We first estimate 3D pose from videos. Especially, we reconstruct a half-body 3D pose to deal with the occlusion problem. Then, we propose a depth regression approach to iteratively regress the depth of a 3D pose. Unlike data-driven approaches, our depth regression approach does not require training data and can be integrated into any 3D pose model. Finally, we exploit the geometric constraints from the point cloud to optimize the 3D trajectory. We evaluated the 3D pose estimation and depth regression modules on the H3.6M datasets. Due to the lack of evaluation datasets, we also built a trajectory dataset to evaluate the trajectory reconstruction performance. Empirical evaluation shows that our framework achieves accurate trajectory reconstruction results on real-world videos. [ABSTRACT FROM AUTHOR]

Efficient 3-D mapping provides useful and detailed 3-D data for many applications. In this letter, we present a multisensor calibration and mapping method, to provide highly efficient and relatively accurate colored mapping for GPS-/global navigation satellite system-denied environments. The sensor data include 3-D laser scanning point clouds and camera images. A simultaneous localization and mapping (SLAM)-assisted calibration method is first proposed for multiple multibeam light detection and ranging (LiDAR) and multiple camera calibration. An improved SLAM method with loop closure is proposed for 3-D mapping. With the proposed calibration and mapping methods, centimeter-level colored point clouds can be obtained efficiently. The proposed method was tested with both backpacked and car-mounted systems on indoor and outdoor scenes. Experimental results show the effectiveness and efficiency of the proposed calibration and mapping methods. [ABSTRACT FROM AUTHOR]

This letter presents a line structure-based method for integration of centimeter-level indoor backpacked scanning point clouds and millimeter-level outdoor terrestrial laser scanning point clouds. Using 3-D lines for registration, instead of matching points directly, can improve the robustness of the method and adapt to multisource point cloud data of different qualities. Considering the limited overlapping between indoor and outdoor scenes, line structures are extracted from overlapped wall areas that may be included in interior and exterior data. Here, a patch-based method labels a point cloud into wall, ceiling, floor categories, as well as assigning the candidate overlapping walls. Then, lines structures are extracted from the wall plane point cloud. Potential door and window line structures are detected and refined for point cloud registration. Last, an iterative closest point-based method is used to fine tune the registration results. Our results show that the proposed method effectively integrates a promising map of indoor and outdoor scenes. [ABSTRACT FROM AUTHOR]

We introduce HiSC4D, a novel Human-centered interaction and 4D Scene Capture method, aimed at accurately and efficiently creating a dynamic digital world, containing large-scale indoor-outdoor scenes, diverse human motions, rich human-human interactions, and human-environment interactions. By utilizing body-mounted IMUs and a head-mounted LiDAR, HiSC4D can capture egocentric human motions in unconstrained space without the need for external devices and pre-built maps. This affords great flexibility and accessibility for human-centered interaction and 4D scene capturing in various environments. Taking into account that IMUs can capture human spatially unrestricted poses but are prone to drifting for long-period using, and while LiDAR is stable for global localization but rough for local positions and orientations, HiSC4D employs a joint optimization method, harmonizing all sensors and utilizing environment cues, yielding promising results for long-term capture in large scenes. To promote research of egocentric human interaction in large scenes and facilitate downstream tasks, we also present a dataset, containing 8 sequences in 4 large scenes (200 to 5,000 m 2 ), providing 36k frames of accurate 4D human motions with SMPL annotations and dynamic scenes, 31k frames of cropped human point clouds, and scene mesh of the environment. A variety of scenarios, such as the basketball gym and commercial street, alongside challenging human motions, such as daily greeting, one-on-one basketball playing, and tour guiding, demonstrate the effectiveness and the generalization ability of HiSC4D. The dataset and code will be publicly available for research purposes.

In situ tailoring of two-dimensional materials' phases under external stimulus facilitates the manipulation of their properties for electronic, quantum and energy applications. However, current methods are mainly limited to the transitions among phases with unchanged chemical stoichiometry. Here we propose on-device phase engineering that allows us to realize various lattice phases with distinct chemical stoichiometries. Using palladium and selenide as a model system, we show that a PdSe 2 channel with prepatterned Pd electrodes can be transformed into Pd 17 Se 15 and Pd 4 Se by thermally tailoring the chemical composition ratio of the channel. Different phase configurations can be obtained by precisely controlling the thickness and spacing of the electrodes. The device can be thus engineered to implement versatile functions in situ, such as exhibiting superconducting behaviour and achieving ultralow-contact resistance, as well as customizing the synthesis of electrocatalysts. The proposed on-device phase engineering approach exhibits a universal mechanism and can be expanded to 29 element combinations between a metal and chalcogen. Our work highlights on-device phase engineering as a promising research approach through which to exploit fundamental properties as well as their applications., (© 2024. The Author(s), under exclusive licence to Springer Nature Limited.)

The building block of in-memory computing with spintronic devices is mainly based on the magnetic tunnel junction with perpendicular interfacial anisotropy (p-MTJ). The resulting asymmetric write and readout operations impose challenges in downscaling and direct cascadability of p-MTJ devices. Here, we propose that a previously unimplemented symmetric write and readout mechanism can be realized in perpendicular-anisotropy spin-orbit (PASO) quantum materials based on Fe 3 GeTe 2 and WTe 2 . We demonstrate that field-free and deterministic reversal of the perpendicular magnetization can be achieved using unconventional charge-to- z -spin conversion. The resulting magnetic state can be readily probed with its intrinsic inverse process, i.e., z -spin-to-charge conversion. Using the PASO quantum material as a fundamental building block, we implement the functionally complete set of logic-in-memory operations and a more complex nonvolatile half-adder logic function. Our work highlights the potential of PASO quantum materials for the development of scalable energy-efficient and ultrafast spintronic computing.

Introduction: Current evidence indicates endovascular intervention is a safe and effective treatment for peripheral artery disease of the lower extremity. However, the clinical outcome of endovascular intervention for femoropopliteal lesions has been shown to be affected by the status of tibial runoff. It remains unclear whether endovascular intervention for tibial runoff is associated with additional benefits., Methods and Analysis: This prospective, multicenter, real-world observational study is carried out from January 2021 to December 2022 in 8 designated centers across China with an estimated sample size of 1200 patients with severe femoropopliteal disease. The pre-procedural status of tibial runoff is evaluated with the modified SVS score and categorized as good (SVS <5), compromised (SVS 5-10) or poor (SVS >10). Whether the patient will be treated with endovascular intervention for tibial runoff is determined by the treating vascular surgeons. Patients are dichotomized into the intervention group and the non-intervention group, with each group further divided into the good, compromised and poor tibial run-off subgroup, yielding 6 subgroups in total. Patients within various subgroups are compared with regard to the primary patency rate of the femoropopliteal artery, changes in quality of life, changes of Rutherford category, improvement of the Wound, Ischemia, and Foot Infection Classification, and incidence of major adverse events over 24-months follow-up. The results of this study may provide important information to help vascular sspecialists to decide whether the tibial runoff should be endovascularly intervened and which patient population benefits most from tibial runoff intervention., Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT04675632?id=NCT04675632&draw=2&rank=1, NCT04675632., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. Reviewer XC declared a shared affiliation with two of the authors MY and YD to the handling editor at time of review., (Copyright © 2022 Liu, Wang, Wu, Fen, Guo, Li, Fang, Sang, Dai, He and Ye.)