Advances and Perspectives on Manganese-Doped Topological Insulators: Magnetic Properties and Quantum Applications

Topological insulators (TIs) are a remarkable class of materials with conductive surfaces or edges that are protected by time-reversal symmetry (TRS), positioning them as strong candidates for applications in spintronics and quantum technologies. Doping three-dimensional (3D) TIs and thin films with magnetic elements like manganese (Mn) has proven to be an effective method for breaking TRS and creating a band gap at the Dirac point. This engineered gap enables exploration of various quantum phenomena, offering deeper insights into spin physics and expanding the potential for advanced TI-based devices. Manganese doping not only induces magnetic ordering but also modifies the electronic structure of TIs, making it an efficient tool for tailoring magnetic and electronic properties to meet application-specific requirements. The gapped surface states of Mn-doped TIs hold promising applications in quantum computing, through phenomena like the quantum anomalous Hall effect, and in spintronics, where precise spin current control is crucial. This review provides a comprehensive overview of recent progress in Mn-doped TIs, examining both theoretical and experimental perspectives on their magnetic and electronic properties and exploring their potential for quantum applications. By identifying current challenges and highlighting future opportunities, this work aims to guide the development of Mn-doped TIs for next-generation quantum and spintronic technologies.