Resource theory of imaginarity in distributed scenarios
Kang‐Da Wu, Tulja Varun Kondra, Carlo Maria Scandolo, Swapan Rana, Guo‐Yong Xiang, Chuan‐Feng Li, Guang‐Can Guo, Alexander Streltsov · Communications Physics · 2024
Abstract The resource theory of imaginarity studies the operational value of imaginary parts in quantum states, operations, and measurements. Here we introduce and study the distillation and conversion of imaginarity in distributed scenario. This arises naturally in bipartite systems where both parties work together to generate the maximum possible imaginarity on one of the subsystems. We give exact solutions to this problem for general qubit states and pure states of arbitrary dimension. We present a scenario that demonstrates the operational advantage of imaginarity: the discrimination of quantum channels without the aid of an ancillary system. We then link this scenario to local operations and classical communications(LOCC) discrimination of bipartite states. We experimentally demonstrate the relevant assisted distillation protocol, and show the usefulness of imaginarity in the aforementioned two tasks.