Disti-Mator, an entanglement distillation-based state estimator

Abstract Minimizing both experimental effort and consumption of valuable quantum resources in state estimation is vital in practical quantum information processing. Typically, estimation protocols are independently implemented from other protocols, incurring additional resource cost. Here, we explore the estimation of states as an additional benefit of entanglement distillation protocols. We show that the Bell-diagonal parameters of any undistilled state can be efficiently estimated solely from the measurement statistics of probabilistic distillation protocols. We further introduce the distillation-based state estimator ‘Disti-Mator’ designed for a realistic experimental setting, and exhibit its robustness through numerical simulations. Our results demonstrate that a separate estimation protocol can be circumvented whenever distillation is an indispensable communication-based task.