Correspondence between entangled states and entangled bases under local transformations
Abstract
We investigate whether pure entangled states can be associated to a measurement basis in which all vectors are local unitary transformations of the original state. We prove that for bipartite states with a local dimension that is either or , every state corresponds to a basis. Via numerics we strongly evidence the same conclusion also for two qutrits and three qubits. However, for some states of four qubits we are unable to find a basis, leading us to conjecture that not all quantum states admit a corresponding measurement. Furthermore, we investigate whether there can exist a set of local unitaries that transform \textit{any} state into a basis. While we show that such a state-independent construction cannot exist for general quantum states, we prove that it does exist for real-valued -qubit states if and only if , and that such constructions are impossible for any multipartite system of an odd local dimension. Our results suggest a rich relationship between entangled states and iso-entangled measurements with a strong dependence on both particle numbers and dimension.
Cite
@article{arxiv.2301.13285,
title = {Correspondence between entangled states and entangled bases under local transformations},
author = {Florian Pimpel and Martin J. Renner and Armin Tavakoli},
journal= {arXiv preprint arXiv:2301.13285},
year = {2023}
}