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Guibin Lan

Publications and source records attributed to Guibin Lan.

3 recordsLinked to original sources

Stimulated Magnonic Frequency Combs

Magnonic frequency combs, characterized by a series of discrete frequency lines, have emerged as a promising frontier in magnon spintronics, with potential applications in advanced information processing and sensing technologies. Although the three-magnon scattering process is widely recognized as a fundamental mechanism for generating these combs, its experimental realization has remained challenging due to the high threshold power and strict conservation of momentum and energy. In this work, we propose a novel mechanism for the stimulated generation of magnonic frequency combs that overcomes these limitations. Our approach offers precise and efficient control over key comb properties, including spacing between spectral lines and the number of lines, marking a significant advancement in the field. We substantiate this mechanism through a robust combination of theoretical modeling, micromagnetic simulations, and experimental validation. This study not only demonstrates the feasibility of our method but also opens new pathways for integrating magnonic frequency combs into practical spintronic devices.

cond-mat.mes-hall

Robust field-free switching using large unconventional spin-orbit torque in an all-van der Waals heterostructure

The emerging all-van der Waals (vdW) magnetic heterostructure provides a new platform to control the magnetization by the electric field beyond the traditional spintronics devices. One promising strategy is using unconventional spin-orbit torque (SOT) exerted by the out-of-plane polarized spin current to enable deterministic magnetization switching and enhance the switching efficiency. However, in all-vdW heterostructures, large unconventional SOT remains elusive and the robustness of the field-free switching against external magnetic field hasn't been examined, which hinder further applications. Here we demonstrate the field-free switching in an all-vdW heterostructure combining a type-II Weyl semimetal TaIrTe4 and above-room-temperature ferromagnet Fe3GaTe2. The fully field-free switching can be achieved at 2.56 x 10^10 A per m2 at 300K and a large SOT effective field efficiency of the out-of-plane polarized spin current generated by TaIrTe4 is determined to be 0.37. Moreover, we find that the switching polarity cannot be changed until the external in-plane magnetic field reaches 252mT, indicating a robust switching against the magnetic field. The numerical simulation suggests the large unconventional SOT reduces the switching current density and enhances the robustness of the switching. Our work shows that all-vdW heterostructures are promising candidates for future highly efficient and stable SOT-based devices.

cond-mat.mes-hall

Broad-Wavevector Spin Pumping of Flat-Band Magnons

We report the experimental observation of large spin pumping signals in YIG/Pt system driven by broad-wavevector spin-wave spin current. 280 nm-wide microwave inductive antennas offer broad-wavevector excitation which, in combination with quasi-flatband of YIG, allows a large number of magnons to participate in spin pumping at a given frequency. Through comparison with ferromagnetic resonance spin pumping, we attribute the enhancement of the spin current to the multichromatic magnons. The high efficiency of spin current generation enables us to uncover nontrivial propagating properties in ultra-low power regions. Additionally, our study achieves the spatially separated detection of magnons, allowing the direct extraction of the decay length. The synergistic combination of the capability of broad-wavevector excitation, enhanced voltage signals, and nonlocal detection provides a new avenue for the electrical exploration of spin waves dynamics.

cond-mat.mes-hall