Research progress of robust magnetic resonance wireless power transfer based on topological physics

Magnetic resonance wireless power transfer (WPT) has gradually become a popular research topic of near-field regulation in recent years, with wide application scenarios in mobile phones, implantable medical devices, electric vehicles, and many other fields. However, several challenges remain to be addressed. Near-field coupling induces multiple frequency splits, preventing the system from maintaining a fixed operating frequency; the coupled arrays are susceptible to structural errors and parameter perturbations; current research primarily focuses on single-load transmission, the multi-load transmission systems are still underdeveloped; the direction of transmission is difficult to control flexibly. In recent years, photonic artificial microstructures have provided a flexible platform for studying topological physics, driving significant research interest in their fundamental topological characteristics. The most prominent feature of topological structures is their nonzero topological invariants and the robust edge states determined by the bulk-edge correspondence, which can overcome disturbances caused by defects and disorders. Moreover, by modulating the wave function distribution of topological states, energy can be precisely localized, enabling directional WPT. Therefore, implementing topological modes in WPT systems is of significant scientific importance. This review summarizes recent research in topological models for robust WPT, which is divided into three main parts. The first part introduces one-dimensional periodic topological structures, focusing primarily on the significant improvements in transmission efficiency and robustness achieved by utilizing topological edge states in the Su-Schrieffer-Heeger(SSH) model for WPT. Moreover, a composite chain formed by two SSH chains was constructed to realize a higher-order parity-time (PT) symmetric topological model. This approach addresses frequency splitting caused by coupled edge states and exhibits lower power losses in standby mode. The second part discusses several types of aperiodic one-dimensional topological chains. By introducing topological defect states at the interface between two different dimer chain, robust multi-load WPT was achieved. Furthermore, based on the integration of artificial intelligence algorithms, the SSH-like topological model enables more efficient and robust WPT compared to conventional SSH chain. The asymmetric edge states in quasi-periodic Harper chain provide a solution for directional transmission in WPT applications. By introducing nonlinear circuits, this model enables active control of the transfer direction. The third part presents the application of high-order topological corner states in multi-load robust WPT, demonstrating the selective excitation of both symmetric and asymmetric corner modes. Finally, future perspectives on the application of topological modes in WPT systems are discussed. With the development of new physics, the integration of non-Hermitian physics and topological physics holds great promise for achieving simultaneous energy-information transfer, which is expected to enable compatible WPT, wireless communication, and wireless sensing within a single system. Such a fusion technology will offer breakthroughs in efficiency, robustness, and multifunctionality for next-generation wireless systems.