Search for: All records

Abstract Laser-Induced Forward Transfer (LIFT) printing is a highresolution, non-contact, laser-based direct-writing technology suitable for various materials. The LIFT process is limited by its one-to-one correspondence between laser pulses and jet formation, which restricts the printing throughput and complicates scaling for high-speed operations. To address this challenge, we propose a novel strategy to integrate a porous structure below the donor slide in the LIFT system. The porous structure is expected to facilitate the formation of multiple jets from a single laser pulse, thereby overcoming traditional throughput limitations. In this study, we developed a computational fluid dynamics (CFD) model to verify the proposed idea. The findings confirmed that the formation of multiple jets induced by a single laser pulse can be achieved by manipulating the dynamics of bubble expansion within the porous structures. The simulations also demonstrated that variations in the size, spacing, and positioning of the porous structures, along with the initial bubble pressure, can significantly influence jet characteristics. This enables precise control over jet width and length, suggesting a viable approach to achieving high-throughput, high-efficiency LIFT printing through the deployment of porous structures. 

Abstract Current induced spin-orbit torque (SOT) holds great promise for next generation magnetic-memory technology. Field-free SOT switching of perpendicular magnetization requires the breaking of in-plane symmetry, which can be artificially introduced by external magnetic field, exchange coupling or device asymmetry. Recently it has been shown that the exploitation of inherent crystal symmetry offers a simple and potentially efficient route towards field-free switching. However, applying this approach to the benchmark SOT materials such as ferromagnets and heavy metals is challenging. Here, we present a strategy to break the in-plane symmetry of Pt/Co heterostructures by designing the orientation of Burgers vectors of dislocations. We show that the lattice of Pt/Co is tilted by about 1.2° when the Burgers vector has an out-of-plane component. Consequently, a tilted magnetic easy axis is induced and can be tuned from nearly in-plane to out-of-plane, enabling the field-free SOT switching of perpendicular magnetization components at room temperature with a relatively low current density (~10¹¹A/m²) and excellent stability (> 10⁴cycles). This strategy is expected to be applicable to engineer a wide range of symmetry-related functionalities for future electronic and magnetic devices.