The recent emergence of 2D van der Waals magnets down to atomic layer thickness provides an exciting platform for exploring quantum magnetism and spintronics applications. The van der Waals nature stabilizes the long-range ferromagnetic order as a result of magnetic anisotropy. Furthermore, giant tunneling magnetoresistance and electrical control of magnetism have been reported. However, the potential of 2D van der Waals magnets for magnonics, magnon-based spintronics, has not been explored yet. Here, we report the experimental observation of long-distance magnon transport in quasi-twodimensional van der Waals antiferromagnet MnPS3, which demonstrates the 2D magnets as promising material candidates for magnonics. As the 2D MnPS3 thickness decreases, a shorter magnon diffusion length is observed, which could be attributed to the surface-impurity-induced magnon scattering. Our results could pave the way for exploring quantum magnonics phenomena and designing future magnonics devices based on 2D van der Waals magnets. I. INTRODUCTIONThe recent emergence of two-dimensional (2D) van der Waals magnets down to atomic-layer thickness has attracted considerable interest and provided an exciting platform for exploring new physical phenomena in low-dimensional magnetism [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. The long-range ferromagnetic order in 2D magnets has been demonstrated in bilayer Cr2Ge2Te6 and single layer CrI3 as a result of magnetic anisotropy [1,2,16]. Shortly, the potential of such van der Waals ferromagnets for spintronics applications has been intensively explored. For example, giant tunneling magnetoresistance in bilayer CrI3 has been demonstrated [17][18][19], which is much higher compared to conventional single-crystalline-MgO barrier based ferromagnetic tunneling junctions [20,21].The important role of magnon-assistant tunneling through thin CrBr3 barriers has been shown in the graphene/CrBr3/graphene heterostructures [22]. Because of their 2D nature, efficient electrical control of magnetism in 2D ferromagnetic materials has also been explored [3,[23][24][25][26], which provides an alternative route towards high-temperature ferromagnetic semiconductors [27,28]. Furthermore, room-temperature 2D ferromagnetism in monolayer van der Waals magnet has also been demonstrated in epitaxial films and ionic liquid gated flakes [8,9,25].Magnonics refers to the magnon-based spintronics, the use of magnon-mediated spin current for information logic and computing applications [29]. One of the major research directions is to search the suitable magnon transport channel materials, which can propagate magnons over a long Sciences (Grant No. XDB28020100). References:[1]C.

We report the experimental investigation of the superconductor-metal quantum phase transition of the EuO/KTaO3 interface. Around the transition, a divergence of the dynamical critical exponent is observed, which supports the quantum Griffiths singularity in the EuO/KTaO3 interface. The quantum Griffiths singularity could be attributed to large rare superconducting regions and quenched disorders at the interface. Our results could pave the way for studying the exotic superconducting properties at the EuO/KTaO3 interface.

Fundamental symmetry breaking and relativistic spin–orbit coupling give rise to fascinating phenomena in quantum materials. Of particular interest are the interfaces between ferromagnets and common s-wave superconductors, where the emergent spin-orbit fields support elusive spin-triplet superconductivity, crucial for superconducting spintronics and topologically-protected Majorana bound states. Here, we report the observation of large magnetoresistances at the interface between a quasi-two-dimensional van der Waals ferromagnet Fe0.29TaS2 and a conventional s-wave superconductor NbN, which provides the possible experimental evidence for the spin-triplet Andreev reflection and induced spin-triplet superconductivity at ferromagnet/superconductor interface arising from Rashba spin-orbit coupling. The temperature, voltage, and interfacial barrier dependences of the magnetoresistance further support the induced spin-triplet superconductivity and spin-triplet Andreev reflection. This discovery, together with the impressive advances in two-dimensional van der Waals ferromagnets, opens an important opportunity to design and probe superconducting interfaces with exotic properties.

We report the critical role of La doping in the topological Hall effect observed in LaxEu1-xO thin films (~ 50 nm) grown by molecular beam epitaxy. When the La doping exceeds 0.036, topological Hall effect emerges, which we attribute to the formation of magnetic skyrmions.Besides, the La doping is found to play a critical role in determining the phases, densities, and sizes of the skyrmions in the LaxEu1-xO thin films. The maximum region of the skyrmion phase diagram is observed on the La0.1Eu0.9O thin film. As the La doping increases, the skyrmion density increases while the skyrmion size decreases. Our findings demonstrate the important role of La doping for the skyrmions in EuO films, which could be important for future studies of magnetic skyrmions in Heisenberg ferromagnets.