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Quantum teleportation plays a significant role in the field of quantum communication. This paper investigates quantum teleportation through a noisy environment by using GHZ state and non-standard W state as quantum channels. We analyze the efficiency of quantum teleportation by solving analytically a master equation in Lindblad form. Following the quantum teleportation protocol, we obtain the fidelity of quantum teleportation as a function of evolution time. The calculation results show that the teleportation fidelity using non-standard W is higher in comparison to GHZ state at the same evolution time. Moreover, we consider the efficiency of teleportation with weak measurements and reverse quantum measurement under amplitude damping noise. Our analysis suggests that the teleportation fidelity using non-standard W is also more robust to noise than GHZ state in the same conditions. Interestingly, we found that weak measurement and its reverse operation have no positive effect on the efficiency of quantum teleportation by using GHZ and non-standard W state in the amplitude damping noise environment. In addition, we also demonstrate the efficiency of quantum teleportation can be improved by making minor modifications to the protocol. [ABSTRACT FROM AUTHOR]

We use weak measurement (WM) and quantum measurement reversal (QMR) techniques to suppress the degradation of genuine nonlocality of a special class of three-qubit "X" states when they suffer from the amplitude damping noise. We choose the maximal violation of the Svetlichny inequality to quantify the genuine nonlocality of states in this paper. We analyse mathematically the sufficient and necessary condition for weak measurement or QMR to enhance the genuine nonlocality of such "X" states. We propose a specific protection scheme combined WM with QMR for such states, and calculate the maximal genuine nonlocality reached by our scheme as well as the success probability. We apply our scheme to the GHZ-like states and the Werner-type states to show the protection effect. [ABSTRACT FROM AUTHOR]

We study separability problem using general symmetric informationally complete measurements and propose separability criteria in $$\mathbb {C}^{d_{1}}\otimes \mathbb {C}^{d_{2}}$$ and $$\mathbb {C}^{d_{1}}\otimes \mathbb {C}^{d_{2}}\cdots \otimes \mathbb {C}^{d_{n}}$$ . Our criteria just require less local measurements and provide experimental implementation in detecting entanglement of unknown quantum states. [ABSTRACT FROM AUTHOR]