The implementation of quantum routers is an important and desired task in quantum information science, since quantum routers are important components of quantum networks. Here we propose a scheme for implementing single-photon routers in a waveguide-QED system, which consists of two coupled two-level atoms coupled to two waveguides to form a four-port quantum device. We obtain the exact analytical expressions of the single-photon scattering amplitudes using the real-space method. By taking into account or disregarding the propagating time of photons between two coupling points, we consider the system working in the Markovian and non-Markovian regimes, respectively. In addition, we introduce the chiral coupling, which breaks the symmetry of the waveguide model, to manipulate the transmission of single photons. We find that when the system works in the non-Markovian regime, the single photon can be transmitted on demand by adjusting the asymmetry coefficient. More interestingly, the complete single-photon routing in this device does not require an ideal chiral coupling, loosening the photon transport conditions. This work should motivate studies concerning the nonreciprocal and chiral quantum devices in the waveguide-QED platform.

Close

PrevNext

View figure in article

• Quantum optics
• Waveguides