Twist-induced Casimir Attractive-Repulsive Transition Based on Lithium Iodate

Twisted systems exhibiting unique electronic and mechanical properties are valuable in quantum physics and material science. Inspired by the concept of twistronics, we investigate the Casimir interaction in the twisted system. We delve into the behavior of the Casimir force within a system comprising layers of lithium iodate (LiIO3), separated by a composite medium of nanoparticles dispersed in a liquid. A notable observation is that the Casimir force undergoes a transition from attractive to repulsive, arising in the relative rotation of the LiIO3 at the Casimir magic twist angle. The transitions are induced by quasispindle dispersion and the competition between repulsion and attraction in wavevector space. This work combines macroscopic geometric configurations with microscopic quantum interactions, marks a step in the tunable Casimir attractive–repulsive transition, and is helpful for switchable nanoscale devices with ultralow static friction.