Deciphering Orbital and Spin-Resolved Transmission Spectra via the NEGF Formalism

By using the Non-equilibrium Green's function (NEGF) formalism to study charge and spin transport in a quantum ribbon governed by two contrasting mechanisms: magnetic flux-induced orbital quantization described by the 1D effective orbital model, and internal exchange interactions described by the long-range RKKY Hamiltonian. By examining the energy-dependent transport response, we compare how these mechanisms affect the overall transport behavior of the system. The orbital effect leads to flux-controlled energy gaps and modulated charge transport, whereas RKKY interactions induce exchange-driven band modifications. Additionally, introducing an inelastic scattering parameter breaks phase coherence, driving a crossover from ballistic to diffusive transport, thereby highlighting the role of dephasing in realistic quantum devices.