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arXiv · 1805.00806

Characterizing quantum phase transition by teleportation

Meng-He Wu·Yi Ling·Fu-Wen Shu·Wen-Cong Gan
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Abstract

In this paper we provide a novel way to explore the relation between quantum teleportation and quantum phase transition. We construct a quantum channel with a mixed state which is made from one dimensional quantum Ising chain with infinite length, and then consider the teleportation with the use of entangled Werner states as input qubits. The fidelity as a figure of merit to measure how well the quantum state is transferred is studied numerically. Remarkably we find the first-order derivative of the fidelity with respect to the parameter in quantum Ising chain exhibits a logarithmic divergence at the quantum critical point. The implications of this phenomenon and possible applications are also briefly discussed.

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Meng-He Wu, Yi Ling, Fu-Wen Shu, Wen-Cong Gan. 2018-05-02. Characterizing quantum phase transition by teleportation. https://doi.org/10.1016/j.physleta.2018.02.023

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