Absolute Non-Violation of a Three-Setting Steering Inequality by Two-Qubit States
arXiv:1612.07644 · doi:10.1007/s11128-017-1734-4
Abstract
Steerability is a characteristic nonlocal trait of quantum states lying in between entanglement and Bell nonlocality. A given quantum state is considered to be steerable if it violates a suitably chosen steering inequality. A quantum state which otherwise satisfies a certain inequality can violate the inequality under a global change of basis i.e, if the state is transformed by a nonlocal unitary operation. Intriguingly there are states which preserve their non-violation(pertaining to the said inequality) under any global unitary operation. The present work explores the effect of global unitary operations on the steering ability of a quantum state which live in two qubits. We characterize such states in terms of a necessary and sufficient condition on their spectrum. Such states are also characterized in terms of some analytic characteristics of the set to which they belong. Looking back at steerability the present work also provides a relation between steerability and quantum teleportation together with the derivation of a result related to the optimal violation of steering inequality . An analytic estimation of the size of such non-violating states in terms of purity is also obtained. Interestingly the estimation in terms of purity also gives a necessary and sufficient condition in terms of bloch parameters of the state. Illustrations from some signature class of quantum states further underscore our observations.
Comments are welcome, Two figures
References in corpus (15)
- Entanglement detection
- Steering, Entanglement, Nonlocality, and the EPR Paradox
- Experimental criteria for steering and the Einstein-Podolsky-Rosen paradox
- Entanglement, EPR-correlations, Bell-nonlocality, and Steering
- Testing the Hilbert space dimension
- Device-independent tests of classical and quantum dimensions
- Joint measurability of generalized measurements implies classicality
- Experimental observation of an entire family of four-photon entangled states
- Quantum steering ellipsoids, extremal physical states and monogamy
- Nonlocality and conflicting interest games
- Optimal Measurements for Tests of EPR-Steering with No Detection Loophole using Two-Qubit Werner States
- All two-qubit states that are steerable via Clauser-Horne-Shimony-Holt-type correlations are Bell nonlocal
- Nonlocal correlations: Fair and Unfair Strategies in Bayesian Game
- Hardy's nonlocality argument as witness for post-quantum correlation
- Complete Entanglement Witness for Quantum Teleportation
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- Hidden Steering Nonlocality in Quantum Networks
- Breaking absolute separability with quantum switch
- Any Two Qubit State Has Non Zero Quantum Discord Under Global Unitary Operations