Coherent control of photomagnetic back-switching by double-pump laser pulses

The control of nonthermal all-optical magnetization switching, under a regime of a train of identical laser pulses, opens up opportunities for ultrafast magnetic recording. Here, we investigate the photomagnetic back-switching capabilities of the write and erase magnetic domain pattern using double-pump pulse excitations in an iron-garnet film with pure cubic magnetocrystalline symmetry. It is essential to note that forward and backward magnetization switching is achievable in two distinctive scenarios: using identical linearly polarized laser pulses and with pulses having orthogonal polarization planes. By observing the switch of magnetization at domains independent of the initial state, one can nonthermally toggle the magnetization, equivalent to the XOR logic operation, at frequencies reaching up to 50 GHz.