In composite photosynthetic systems, one most primary promise is to pursue the effect coupling among light harvesting, charge transfer, and catalytic kinetics. Herein, this study designs the reduced carbon dots (r‐CDs) as both photon harvesters and photoelectron donors in combination with the platinum (Pt) clusters and fabricated the function‐integrated r‐CD/Pt photocatalyst through a photochemical route to control the anchoring of Pt clusters on r‐CDs' surface for solar‐driven hydrogen (H2) generation. In the obtained r‐CD/Pt composite, the r‐CDs absorb solar photons and transform them into energetic electrons, which transfer to the Pt clusters with favorable charge separation for H2 evolution reaction (HER). As a result, the efficient coupling of respective natures from r‐CDs in photon harvesting and Pt in proton reduction is achieved through well‐steered photoelectron transfer in the r‐CD/Pt system to cultivate a remarkable and stable photocatalytic H2 evolution activity with an average rate of 681 µmol g−1 h−1. This work integrates two functional components into an effective HER photocatalyst and gains deep insights into the regulation of the function coupling in composite photosynthetic systems.

Dynamics of multiple transverse walls (TWs) in a magnetic nanostripe is studied by micromagnetic simulations. It shows that, when TWs are arranged in a stripe with same orientation, they will attract each other and finally annihilate. However, when adjacent TWs are arranged with opposite orientation, a metastable complex wall can be formed, e.g., two TWs lead to 360o wall. For three or more TWs, the formed complex wall includes a number of 360o substructures, which is called multiple 360o structure (M360S) here. The M360S itself may be used to store multiple logical data since each 360o substructure can act as logical ”0” or ”1”. On the other hand, the M360S may behave like single TW under an applied current, namely, the M360S can be driven steadily by current like that of single TW. A parity effect of the number of 360o substructures on the critical current for the annihilation is found. Namely, when the number is odd or even, the critical current increase or decrease with the increasing of the number, respectively. The parity effect is relevant to the out-of-plane magnetic moment of the M360S.

Domain wall motion (DWM) by spin waves (SWs) in different waveforms in a magnetic nanostripe is investigated via micromagnetic simulations. Diversified DWMs are observed. It is found that SW harmonic drives DWM most efficiently and irregular SW may cause abnormal excitation spectrum for DWM in the low-frequency range. We prove that SW harmonic is the basic element when interacting with DW and causes simple creeping motion of DW (i.e. forward propagation of DW accompanied with oscillation) with the same frequency as applied SW harmonic. Under irregular/polychromatic SW, DW makes responses to the energies carried by constituent SW harmonics, instead of overall exhibited torques, and simultaneously conducts multiple creeping motions. This finding enables the analysis for the induced DWM under arbitrary SW. Mapping of SW inside DW reveals that the simple creeping motion is due to real-space expansion and contraction inside DW and the monolithic translation of DW. It is further elucidated that the former relates to the transmitting of spin torques of SW through DW and the latter corresponds to the absorption of spin torques by DW. The overall absorbed spin torques point to direction same as SW propagation and drive DW forward. In addition, the absorption mechanism is evidenced by the well agreement between absorption of SW and averaged velocity of DW. various magnetic structures. In addition, the ability to assist other approaches for improved performance in DWM gives it an extra advantage [50,51].On the other hand, the interplay between SW and DW remains interesting in fundamental physics. Although great effort has been made in understanding the basic characteristics of SW-induced DWM in terms of both theoretical analysis [34,35,[37][38][39]41] and micromagnetic simulations [32-36, 40, 42], the precise picture in dynamics was never determined. So far, two major mechanisms were proposed: magnonic spin-transfer torque (STT) [34] and magnonic linear momentum transfer torque (LMTT) [11,35]. In STT (for a simplified 1D model), linearization on Landau-Lifshitz-Gilbert (LLG) equation gives a solution of reflectionless propagating SW described by a Schrodinger equation. The obtained SW carries a constant magnon current transmitting through DW. Magnons can be viewed as spin-1 bosons with angular momentum ±ÿ and linear momentum ÿk. As a magnon passes through the DW, its spin is changed by 2ÿ; according to the conservation of angular momentum, the spin of 2ÿ must be transferred to DW, which further results in the backward motion of DW with respect to SW propagation [34,41]. On the other hand, what concerns the LMTT theory is the conservation law for linear momentum. LMTT was proposed to explain cases with reflection. Reflected magnon reverses its wave vector k in sign. That is, the linear momentum is changed by 2ÿk. The transfer of linear momentum to DW rewrites the effective field in LLG and causes forward motion of DW [35,42]. STT and LMTT can only be partially correct due to the fact that SW transmission varies with frequenc...

In a two closely spaced nanostripes system, the coupled vortex wall undergoes a spring-like oscillatory motion (SOM) when current is applied to both nanostripes in opposite directions. The SOM may vanish, when the current density is larger than a critical value. The critical current density for destroying the SOM decreases as the interstripe spacing increases. However, as the perpendicular anisotropy of the system increases, the critical current density firstly decreases and then increases. Two competitive effects of the perpendicular anisotropy on the SOM are shown. Moreover, diagrams of without oscillation, spring behavior and motionless phases upon the current and the interstripe spacing (or the perpendicular anisotropy) are given.

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