Generation of spin-wave packets by reconfigurable nanomagnonic heterojunctions

Nanomagnonic crystals are magnetic waveguides, the magnetic parameters of which are modulated at the nanoscale. The superlattice structure enables a band structure and magnonic band gaps. Here, we numerically investigate the field tunability of such a magnonic band gap. By subjecting different parts of the nanomagnonic crystal to a field, we realize a magnonic heterojunction. A numerical demonstration of an active modification of the band structure leads to magnonic amplitude modulation in the linear regime and magnonic frequency combs in the nonlinear regime. Our results will offer further opportunities for nanomagnonic crystals and inspire their experimental realization.