Decoherence of Weak Coherent State Under Amplitude Damping

LU Dao-ming

Yan‐Ling Li, Xing Mao Xiao

Heng-Mei Li, Xue-xiang Xu, Hong‐Chun Yuan +3 more

Qiao-Yun Tan, Lin Wang, Jinxiang Li +2 more

Kun-Hong Feng, Yu‐Chi Chen, Ping Zhou

High-dimensional quantum communication plays an important role in long-distance quantum communication. It is shown that two-qubit quantum entanglement can be protected from amplitude damping decoherence. We study the effect of amplitude damping decoherence on two-qubit high-dimensional quantum entanglement. The negativity for high-dimensional quantum entanglement with or without quantum weak measurement and the reversal in amplitude damping decoherence are presented. We found that nonmaximally entangled state may have better performance than maximally entangled state in amplitude damping decoherence. Moreover, we show that arbitrary high-dimensional quantum entanglement can be protected from amplitude damping decoherence by weak measurement and the reversal. The results of our protocol are in agreement with previous analysis for the case of qubits and qutrits.

Xiang-Ping Liao, Mao-Fa Fang, Rong Man-sheng +1 more

We demonstrate a method to protect free-entangled and bound-entangled states in a two-qutrit system under amplitude damping and the generalized amplitude damping channels based on measurement reversal from weak measurement. We find that this scheme can circumvent the distillability sudden death by changing weak measurement strength and the free-entangled and bound-entangled states can be robust against decoherence in amplitude damping case. Moreover, the negativity and realignment negativity almost tend to a constant respectively in spite of sufficiently strong decoherence when weak measurement strength is strong. We also show that under the generalized amplitude damping, the life of free-entangled and bound-entangled states can be prolonged using weak measurements in certain conditions.