In an article published in Physical Review Letters, (L. Lackner, O.A. Egorov, A. Ernzerhof, C. Bennenhei, V.N. Mitryakhin, G. Leibeling, F. Eilenberger, S. Tongay, U. Peschel, M. Esmann and C. Schneider. Phys. Rev. Lett. 135, 166901, 2025) members of the Quantum Materials Research Group have published their research on topologically tunable polaritons based on a two-dimensional crystal in a photonic lattice.

This research breaks through the limitations of static, monolithic samples by emulating a topological SSH lattice in a fully tunable, freely accessible optical resonator. With the ability to manipulate topological modes in situ and reconfigure them in real time, the platform shifts the field from passive observation to active control.

The central innovation of this research lies in the successful emulation of a topological SSH (Su-Schrieffer-Heeger) lattice within a fully tunable, freely accessible optical resonator. Unlike previous implementations based on static, monolithic samples, this platform enables in-situ manipulation of topological modes. This work moves topological photonics from ‘static observation’ to ‘active control.’ By demonstrating that topological lattices can be reconfigured and tuned in real time, it paves the way for advanced nonlinear photonic chips in which light can be controlled and switched with unprecedented robustness.