Nonreciprocal photon blockade and directional amplification in a spinning resonator coupled to a two-level atom

We propose a scheme to realize nonreciprocal photon blockade and directional amplification in a spinning resonator with clockwise and counterclockwise traveling modes coupled to a stationary two-level atom. By manipulating the rotational frequency of the resonator, the two-level atom can be resonant with one of the traveling modes and largely detuned from the other one. Nonreciprocal conventional photon blockade is induced by the difference of the detunings between the two-level atom and the optical modes traveling in different directions. Besides that, nonreciprocal unconventional photon blockade (UPB) based on the quantum interference can also be observed in the system. Based on the mechanism for nonreciprocal UPB, directional amplification of the blockaded photons is predicted by driving the spinning resonator and stationary two-level atom simultaneously. Our proposal will be applicable to achieve highly efficient nonreciprocal single-photon devices for applications in chiral quantum information processing.