aiqbench analysis
This paper advances the theoretical understanding of Schmidt number witnesses within specific faces of bipartite quantum state spaces, refining conditions under which these entanglement detectors exist beyond previously identified bounds. By establishing new existence proofs around projection states at the center of orthogonal subspaces, it contributes directly to the foundational mathematics required for characterizing high-dimensional quantum correlations.
Local geometry for Schmidt number witnesses
arXiv:2608.14199v1 Announce Type: new Abstract: Suppose that $F_E$ is the face of the convex set of all $m\otimes n$ bi-partite states which consists of states with ranges contained in a subspace $E$. For generic subspaces $E$ with a specific dimension, we use the result in [Phys. Rev. A 112 (2025), 032426] to see that there exists a number $\kappa$, depending only on the dimension of $E$, such that there exist Schmidt number $\ell$ witnesses outside of $F_{E^\perp}$ if and only if $\ell\le\kappa$. In this generic case, we show in this paper that there exist Schmidt number $\ell$ witnesses for $\ell>\kappa$ around the projection states located at the center of $F_{E^\perp}$.
Abstract:Suppose that $F_E$ is the face of the convex set of all $m\otimes n$ bi-partite states which consists of states with ranges contained in a subspace $E$. For generic subspaces $E$ with a specific dimension, we use the result in [Phys. Rev. A 112 (2025), 032426] to see that there exists a number $\kappa$, depending only on the dimension of $E$, such that there exist Schmidt number $\ell$ witnesses outside of $F_{E^\perp}$ if and only if $\ell\le\kappa$. In this generic case, we show in this paper that there exist Schmidt number $\ell$ witnesses for $\ell>\kappa$ around the projection states located at the center of $F_{E^\perp}$.
arXiv:2608.14199 [quant-ph]
(or arXiv:2608.14199v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2608.14199 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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Full text under the publisher's open licence · 196 words
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