Magnetic Decoupling for High-Yield, Time-Efficient Microscale Self-Assembly

Self-assembly is a powerful strategy for constructing advanced materials with intricate functionalities, but its practical applications are often hindered by low yields and prolonged assembly times due to the formation of parasitic products and long-lived intermediate states. Traditional methods to overcome these challenges lack selectivity, often disrupting both intermediates and desired products. We address this issue by developing a novel self-assembly platform that employs lithographically patterned magnetic dipoles within rigid particles, coupled with an external magnetic field to drive the assembly process. By precisely controlling the position, orientation, and density of magnetic dipoles via electron-beam lithography, we design intermediate states that strongly couple to the magnetic field, while engineering the final target structures to be magnetically decoupled. This selective coupling enables us to apply dynamic magnetic fields that destabilize undesired intermediates without affecting the stable final products, thereby accelerating assembly kinetics and significantly improving yields. Our approach allows explicit control over particle interactions and assembly pathways, providing new insights into the mechanisms of self-assembly and opening possibilities for constructing advanced materials through programmable self-assembly.