Chiral quantum optics with giant atoms

In quantum optics, it is common to assume that atoms are pointlike objects compared the wavelength of electromagnetic field they interact with. However, this dipole approximation not always valid, e.g., if couple at multiple discrete points. Previous work has shown superconducting qubits coupled a one-dimensional waveguide can behave as such ``giant atoms'' and then through without decohering, phenomenon possible with small atoms. Here, we show decoherence-free interaction also when coupling chiral, i.e., depends on propagation direction light. Furthermore, derive conditions under which giant in chiral architectures exhibit dark states. particular, unlike atoms, reach state even being excited by coherent drive. We driven-dissipative regime, states be populated faster The results presented here lay foundation for applications based simulations networks settings.