Entanglement is a quantum correlation that appears in composite systems and constitutes one of the main resources in quantum information. In optics, parametric down conversion (PDC) in a non-linear crystal is the standard technique to generate entangled photon pairs. However, the statistics of the photon number and time distributions follows, essentially, a Poissonian law that severely restricts the range of practical applications of entangled photon sources based on PDC, e.g., for some quantum cryptography protocols. In this work, we propose a cavity Quantum Electrodynamics (cavity-QED) implementation that deterministically generates polarization-entangled photons pairs and that presents three important features from a practical point of view: (i) it operates with high fidelity even in the bad cavity limit; (ii) it is very robust under fluctuations of the system parameters since it is based on adiabatically following an energy eigenstate; and (iii) the initial field state is the simplest in optical cavity-QED, namely the vacuum state for all cavity modes.
展开▼
