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Wang, Jianli

Publications and source records attributed to Wang, Jianli.

Manipulation of Magnetic Skyrmion in a 2D van der Waals Heterostructure via Both Electric and Magnetic Fields

As a promising candidate for the much-desired low power consumption spintronic devices, 2D magnetic van der Waals material also provides a versatile platform for the design and control of topological spin textures. In this work on WTe 2 /CrCl 3 bilayer van der Waals heterostructures, a complete Néel-type skyrmion–bimeron–ferromagnet phase transition is demonstrated, accompanied by the evolution of the topological number. This cyclic transition, mediated by a perpendicular magnetic field, is largely driven by the competition between the out-of-plane magnetocrystalline anisotropy and magnetic dipole–dipole interaction. In the presence of a driving current, the Néel-type skyrmion gains a higher velocity yet larger skyrmion Hall angle, in comparison to the bimeron. By incorporating a ferroelectric CuInP 2 S 6 monolayer as a substrate, writing and erasing of skyrmions may be regulated using a ferroelectric polarization. Here this work sheds light on a novel approach to the design and control of magnetic skyrmions on 2D van der Waals materials.

multiferroic↗

Entropy-stabilized single-atom Pd catalysts via high-entropy fluorite oxide supports

Single-atom catalysts (SACs) have attracted considerable attention in the catalysis community. However, fabricating intrinsically stable SACs on traditional supports (N-doped carbon, metal oxides, etc.) remains a formidable challenge, especially under high-temperature conditions. Here, we report a novel entropy-driven strategy to stabilize Pd single-atom on the high-entropy fluorite oxides (CeZrHfTiLa)O x (HEFO) as the support by a combination of mechanical milling with calcination at 900 °C. Characterization results reveal that single Pd atoms are incorporated into HEFO (Pd1@HEFO) sublattice by forming stable Pd–O–M bonds (M = Ce/Zr/La). Compared to the traditional support stabilized catalysts such as Pd@CeO 2 , Pd 1 @HEFO affords the improved reducibility of lattice oxygen and the existence of stable Pd–O–M species, thus exhibiting not only higher low-temperature CO oxidation activity but also outstanding resistance to thermal and hydrothermal degradation. This work therefore exemplifies the superiority of high-entropy materials for the preparation of SACs.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Anticorrelation of compressibility and resistivity in a microwave-irradiated two-dimensional electron system

Here, we report our direct study of the compressibility on an ultrahigh mobility two-dimensional electron system ( μ e ~ 1 × 10 7 cm 2 /V s) in GaAs/AlGaAs quantum wells under microwave irradiation. The field penetration current results show that the quantum capacitance oscillates with microwave-induced resistance oscillations, yet, the trend is opposite with respect to the compressibility of equilibrium states in previous theoretical explanations. The anomalous phenomena provide a platform for study on the nonequilibrium system under microwaves. Moreover, the quantum capacitance indication for a multiphoton process around j = 1 / 2 is detected under an intensive microwave below 30 GHz.

77 NANOSCIENCE AND NANOTECHNOLOGY↗