Efficient hyperentanglement purification using a Lambda system coupled with a whispering-gallery-mode microresonator

摘要

Entanglement purification is of great importance in long-distance quantum communications and distributed quantum computations. Here we present an efficient scheme for the hyperentanglement purification (HP) of a two-photon system by using a high-dimensional logical gate device which is composed of atoms and a quantized whispering-gallery-mode microresonator. In the present scheme, one can complete the HP and entanglement storage in one step without resorting to additional qubits. Compared with the conventional HP schemes in which the two-qubit two-dimensional parity-checking measurements are used to correct the bit-flip errors, our scheme, which explored the high-dimensional controlled-flip operation, shows a wide distillation range with a higher fidelity. The remaining resources of the failed HP processing can be used to purify the other pair hyperentangled photons. Therefore, the efficiency of our scheme is higher than the previous schemes. The implementation of our HP is assisted by nitrogen-vacancy centers in optical microresonators, which could be achieved with current techniques. (c) 2018 Optical Society of America