Fig. 1: An illustration of the proposed method for entanglement detection.
From: Symmetry-resolved entanglement detection using partial transpose moments
We assume the experimentally relevant situation of a source producing non-identical but independent copies {ρ1, …, ρN} ("drift''). Randomly chosen unitaries Ui are applied to the qubits of each copy and then measured in the standard basis. Using classical shadows24, these measurement outcomes are post-processed to obtain the moments \({p}_{j}={{{\rm{tr}}}}{({\rho }_{{{{\rm{avg}}}}}^{{{\Gamma }}})}^{j}\). As explained in the main text, we combine those moments to derive inequalities whose violation implies that the state ρavg is NPT, thus showing that at least one of the states ρk produced by the source is entangled. We also show how symmetry-resolution techniques can be used to enhance entanglement detection capabilities.
