Fig. 3: Klein paradox and particle-antiparticle (P-AP) pair productions of synthetic antiferromagnetic (SyAFM) magnons.
Scattering of the incident Ψ+ wave packets with the central wave vector k0 = 500μm−1 by a the Klein step and b the supercritical square barrier induced by a space-varying magnetic field pulse Bz = 2 T. Abundance of Ψ+-Ψ− pairs are produced upon reflection at the barrier’s edges. c Reflection (R) and transmission (T) coefficients of the Ψ+ wave packet by the potential step as a function of the applied magnetic fields Bz. Note that α = 0 is used during the simulations to validate R + T = 1. d Time evolution of the total polarization-charge in the left (x < 1500 nm), interior (1500 < x < 2000 nm), and right (x > 2000 nm) regions across the supercritical square barrier. Now, the finite Gilbert damping α = 0.001 is used. In all simulations the incoming center energy of the Ψ+ wave packet is E = ω(k0). The simulation parameters are the same as in Fig. 2.
