Sanchit Srivastava

We analyze the relation between multipartite entanglement and genuine multipartite nonlocality, characterized by Svetlichny inequality violations, for two families of qubit states. We show that for the generalized GHZ family of states, Svetlichny inequality is not violated when the tangle is less than a threshold for any number of qubits. On the other hand, the maximal slice states always violate the Svetlichny inequality when tangle is nonzero, and the violation increases monotonically with tangle when the number of qubits is even.

We investigate the harvesting of contextuality from the vacuum of a quantum field using Unruh-DeWitt detectors. We show that interactions with the field can endow initially non-contextual detectors with contextuality with respect to Heisenberg-Weyl measurements, as quantified by contextual fraction. The harvested contextuality correlates with the emergence of Wigner function negativity, in agreement with known equivalences between these notions. Our results establish contextuality harvesting as a fundamental phenomenon in relativistic quantum information.

We show that contextuality, a quantum property that defies classical explanations, can serve as a signature of chaos. For a spin system undergoing chaotic dynamics, we demonstrate that violations of Bell-type inequality can effectively differentiate regular and chaotic regions of the phase space, suggesting that the nonclassicality of the system underpins signatures of chaos.