Alladi Ramakrishnan Hall

Sharing of nonlocal advantage of quantum coherence by sequential observers

Shounak Datta

S. N. Bose National Centre for Basic Sciences, Kolkata

Nonlocal advantage of quantum coherence (NAQC) or steerability of local quantum coherence is a strong nonlocal resource based on coherence complementarity relations. In this work, we provide an upper bound on the number of observers who can independently steer the coherence of the observer in the other wing in a scenario where half of an entangled pair of spin- 1/2 particles is shared between a single observer (Bob) in one wing and several observers (Alices) on the other, who can act sequentially and independently of each other. We consider one- parameter dichotomic POVMs for the Alices and mutually unbiased basis in which Bob determines coherence in the case of the maximally entangled bipartite qubit state. We show that not more than one Alice can exhibit NAQC using all measures of quantum coherence uniformly within such framework.

Reference: Phys. Rev. A 98, 042311 (2018)