Classical-driving-assisted entanglement trapping in photonic-crystal waveguides

Abstract

We investigate the exact entanglement dynamics of two classical-driven atoms, each of which is embedded in a single-end photonic crystal waveguide. The finite end of the waveguide behaves as a perfect mirror, forcing part of the emitted light to return back to the atom. The round-trip time between the mirror and the atom is equivalent to the memory time of the open system. It is shown that, the memory time and the classical driving strength are two ingredients whose interplay plays a key role in controlling entanglement. By manipulating the two ingredients, a bound atom–photon state appears in atom–mirror interspace so as to induce entanglement trapping. We also consider the entanglement transfer between different subsystems. We find that, by applying a controllable classical field, the trapped entanglement can be released to the waveguide, hence we can obtain entangled photon pulses directionally. We also discuss a feasible experimental realization of our prediction.