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arXiv · 1508.07382

Scaling of the local quantum uncertainty at quantum phase transitions

I. B. Coulamy·J. H. Warnes·M. S. Sarandy·A. Saguia
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Abstract

We investigate the local quantum uncertainty (LQU) between a block of L qubits and one single qubit in a composite system of n qubits driven through a quantum phase transition (QPT). A first-order QPT is analytically considered through a Hamiltonian implementation of the quantum search. In the case of second-order QPTs, we consider the transverse-field Ising chain via a numerical analysis through density matrix renormalization group. For both cases, we compute the LQU for finite-sizes as a function of L and of the coupling parameter, analyzing its pronounced behavior at the QPT.

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I. B. Coulamy, J. H. Warnes, M. S. Sarandy, A. Saguia. 2016-04-05. Scaling of the local quantum uncertainty at quantum phase transitions. https://doi.org/10.1016/j.physleta.2016.03.026

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