Stackingtronics: Programmable Interlayer Sliding in 2D Materials

The stacking order in two-dimensional (2D) materials reveals a hidden quantum degree of freedom, turning multilayers into platforms for ferroelectricity, magnetism, correlated flat bands, and superconductivity─properties largely apart from monolayer counterparts. This stacking-enabled electronic/magnetic diversity defines <i>stackingtronics</i>, where the interlayer registry operates as a programmable knob for modulating quantum matter and reaching next-generation nanodevices. This review covers stacking-order-induced functionalities, multiphysics coupling, and effective strategies for their manipulations. In situ real-space techniques, capable of resolving multiple states and interlayer sliding dynamics, are highlighted for uncovering the microstructural origin of sliding ferroelectric polarization. Finally, we briefly discuss the key challenges in the synthesis, property optimization, structural dynamics and artificial-intelligence-induced growth-structure-property design frameworks that hold promise for the full potential of <i>stackingtronics</i> in 2D materials.