Absolute Destruction of Nonlocal Resources

Tamal Guha, Bihalan Bhattacharya, Debarshi Das, Some Sankar Bhattacharya, Amit Mukherjee, Arup Roy, Kaushiki Mukherjee, Nirman Ganguly, A. S. Majumdar

Published Jul 5, 2018• 0 citations

OpenAlex

Abstract

Nonlocal quantum states have significant applications as resources in various quantum informational tasks. Environmental interactions may transform a nonlocal state into a local one with or without steerability. This transformed state may again retrieve its steerability or nonlocality under global unitary interaction. However, in certain cases the nonlocal resource is \textit{absolutely} destroyed, i.e., the transformed state \textit{cannot} repossess its steerability or Bell-nonlocality under arbitrary global unitary action. In the present study, modelling environmental interactions through four particular quantum channels, we investigate how the usefulness of a two qubit nonlocal state as resource can be \textit{absolutely} destroyed. Here the Bell-locality and unsteerability of the transformed two qubit state are studied with respect to a particular local realist inequality and a particular steering inequality, respectively.

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