Single-photon transport in waveguides chirally coupled to atoms

Yi-Mei Wang, Jing Li, Jing Lu +1 more

Zeyang Liao, Xiaodong Zeng, Muhammad Suhail Zubairy

Wang

Gang Li, Xue SUN, De-Xiu Qiu +2 more

ABSTRACT We investigate a polarization‐selective transport scheme based on two V‐type atoms chirally coupled to a waveguide, where each atom exhibits polarization‐dependent optical transitions. An external driving field coherently couples the excited states of the atoms, enabling efficient and controllable polarization conversion during photon transport. For an incident photon prepared in a single polarization state, the system exhibits polarization‐dependent unidirectional transmission and reflection, arising from the chiral atom–waveguide interaction. Moreover, the external driving field allows polarization conversion to occur selectively within the transport channels. When the incident photon is prepared in a superposition of polarization states, the system simultaneously realizes polarization‐selective transmission and reflection, with the transport behavior dynamically controlled by the driving field. This scheme provides a tunable platform for directional transport of single photon with different polarization components, offering a versatile platform for photonic systems with simultaneous control over polarization and propagation direction.

Mu-Tian Cheng, Xiao-San Ma, Jiayan Zhang +1 more

We investigate single photon transport in two waveguides coupled to a two-level quantum emitter (QE). With the deduced analytical scattering amplitudes, we show that under condition of the chiral coupling between the QE and the photon in the two waveguides, the QE can play the role of ideal quantum router to redirect a single photon incident from one waveguide into the other waveguide with a probability of 100% in the ideal condition. The influences of cross coupling between two waveguides and dissipations on the routing are also shown.

Teng-Fei Xiao, Junlong Tian, Jinlei Tan +1 more

We investigate single- and two-photon transport in a one-dimensional waveguide chirally coupled to dissipative Rydberg atom pairs. Using the Laplace transform method, we analytically solve the single- and two-photon scattering problems. Our results show that, by leveraging dissipative effects and the chiral coupling structure, the system can act as a perfect single-photon diode, i.e. the transmittance is unity from one side and zero from the other. A two-photon diode is also realized. Interestingly, the transmitted probability density of the diode increases significantly when atomic dissipation is included. Notably, in the absence of dissipation, transmission is primarily due to correlated photons, whereas in the dissipative system, it is dominated by freely propagating photons. Furthermore, the Rydberg coupling between the atoms, which is experimentally tunable, can be used to modulate the diode effect. Finally, we find that reducing the width of the incident photon wavepacket further enhances the transmission probability density of the two-photon diode. The proposed scheme has potential for applications in quantum communication.