C. Jebaratnam

Absolute non-violation of a three-setting steering inequality by two-qubit states

Steerability is a characteristic non-local trait of quantum states lying in between entanglement and Bell non-locality. 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 non-local 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 lives 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.

Operational nonclassicality of local multipartite correlations in the limited-dimensional simulation scenario

For a bipartite local quantum correlation, superlocality refers to the requirement for a larger dimension of the random variable in the classical simulation protocol than that of the quantum states that generate the correlations. In this work, we consider the classical simulation of local tripartite quantum correlations

Characterization of the quantumness of unsteerable tripartite correlations

P

Improvement in device-independent witnessing of genuine tripartite entanglement by local marginals

among three parties

Einstein-Podolsky-Rosen steering cost in the context of extremal boxes

A, B

Cost of Einstein-Podolsky-Rosen steering in the context of extremal boxes

and

One-sided device-independent self-testing of any pure two-qubit entangled state

C

Tripartite-entanglement detection through tripartite quantum steering in one-sided and two-sided device-independent scenarios

. If at least one of the bipartitions

Operational characterization of quantumness of unsteerable bipartite states

(A|BC)

Certifying genuine multipartite entanglement with steering and separability inequalities

,