Decouple optical writing and reading in a single magneto-optic layer

Determine how far optical writing and optical reading can be decoupled within the same GdFeCo magneto-optic layer, while retaining sufficient pump absorption for all-optical switching and reducing probe absorption for readout.

Background

The simulated Si3N4/GdFeCo device uses the same magnetic layer for both functions but at different wavelengths. Probe absorption is substantial, while absorption of the pump is essential because it supplies the heat that drives switching. The authors therefore identify a materials-and-design problem: determine whether wavelength-dependent optical responses, together with changes in composition, thickness, or interaction length, can preserve the write process while reducing the readout penalty.

References

The open question it poses is a sharp one: how far can writing and reading be decoupled in the same layer?

— Self-consistent modelling of all-optical switching and magneto-optic readout in an integrated Si$_3$N$_4$/GdFeCo waveguide  (2608.22969 - Mulyana et al., 24 Aug 2026) in Section 4, subsection “Readout-suppression hierarchy”