International audienceThe recent realization of topological phases in insulators and superconductors has raised the prospects to advance robust quantum technologies. The desire to demonstrate the underlying topological features with a high level of control has given incentive to explore optical platforms for analogous realizations. Here we show that the functionality of optical systems can be enhanced by combining topological protection with non-hermitian symmetries that do not have an electronic counterpart. This is achieved by combining parity-time symmetric losses with a unique feature of topologically induced interface states, namely, that they break a sublattice symmetry. This property isolates the state from the losses and enhances its visibility both in the frequency and in the time domain
