精确催化无法克服远程Wigner负性的高斯导引障碍
Exact Catalysis Cannot Overcome the Gaussian-Steering Barrier for Remote Wigner Negativity
浏览论文内容
中文总结 AI 辅助
本文证明，即使借助多副本、辅助量子比特或精确返还的催化剂，高斯导引仍是远程Wigner负性不可逾越的障碍，并引入导引负性这一单调量来严格界定其界限。
中文摘要 AI 辅助
高斯导引为远距离产生Wigner负性设定了一个尖锐的阈值。只有当Alice能够通过高斯测量导引Bob时，Bob的测量才能使共享高斯态中Alice的部分变为Wigner负性。我们探究当Alice仅限于高斯操作时，多副本、辅助量子比特或催化剂能否消除这一要求。我们引入了导引负性（steered negativity），这是一个乘法单调量，其对数对于高斯态等于高斯可导引性。它限制了Bob能够预示的负性，并排除了通过副本、Bob的辅助量子比特以及自身无远程负性的催化剂进行激活的可能性。对于严格不可导引的高斯态以及单轮前馈至Alice的高斯酉操作，我们进一步证明，即使Wigner负性或可导引的催化剂，若被精确返还，也无法提供帮助。因此，高斯导引在单副本设置之外仍然是远程Wigner负性的一个障碍。
英文摘要
Gaussian steering sets a sharp threshold for creating Wigner negativity at a distance. A measurement by Bob can make Alice's part of a shared Gaussian state Wigner negative only if Alice can steer him with Gaussian measurements. We ask whether multiple copies, ancillas, or catalysts can lift this requirement when Alice is restricted to Gaussian operations. We introduce the steered negativity, a multiplicative monotone whose logarithm equals the Gaussian steerability for Gaussian states. It bounds the negativity that Bob can herald and rules out activation by copies, by ancillas of Bob, and by catalysts without remote negativity of their own. For a strictly unsteerable Gaussian state and a single round of feed-forward to a Gaussian unitary of Alice, we further prove that even a Wigner-negative or steerable catalyst cannot help if it is returned exactly. Gaussian steering thus remains a barrier to remote Wigner negativity beyond the single-copy setting.
发表机构
- S. N. Bose National Centre for Basic Sciences（S.N. 玻色基础科学国家中心）
机构由 AI 辅助整理，请以论文原文为准。
