Investigating Quantum Spin-Textures Using Universal MJ Hamiltonians

This work introduces a pair of novel universal MJ spintronic models that precisely mirror the complex spin textures observed in spintronic materials. The spin-orbit coupled (SOC) Hamiltonians H_MJ1 and H_MJ2 reveal a range of novel and intriguing spin phenomena by modulating spin-orbit interactions. The Hamiltonian H_MJ1 reshapes the existing paradigm, providing a more robust and versatile framework than the Hamiltonian H_RD, with the potential to catalyze new advancements in the study of quantum materials. H_MJ1 encapsulates two distinct spin textures: a unidirectional, momentum-independent persistent spin texture (PST), and a bidirectional (partial) PST. In contrast Hamiltonian H_MJ2 portrays a spiral spin texture, drawing a conceptual link to the cosmological process of expansion and contraction, mirrored within a two-dimensional quantum framework. We also explore the fundamental aspects of earlier analytical models that underpin the construction of the present MJ spintronic model. The physical interpretations of these models are illustrated graphically, and the emerging spin phenomena resulting from complex SOC are elucidated using a simple vector model.