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In the system of a pair of quantum-entangled neutral kaons from meson decays, when one kaon collapses into the $K_S$ state, the other will collapse instantaneously into the $K_L$ state due to entanglement and nonlocality. However, if the alternative hypothesis is correct and there's a time window during which one kaon is unaware that the other has decayed, some quantum mechanically prohibited $K_SK_S$ decays may occur. We calculate the branching ratios of $K_SK_S$ in vector meson decays under the locality hypothesis and compare them with experimental results. We show that the branching ratio of $J/\psi\rightarrow K_SK_S$ under locality assumption is already excluded by the BESIII experimental upper limit. Additional experimental results are proposed to perform this test in the future., Comment: 7 pages, 3 figures, 1 table

Array-patterned CoPd-based heterostructures are created through e-beam lithography and plasma pretreatment that induces oxidation with depth gradient in the CoPd alloy films, breaking the central symmetry of the structure. Effects on the magnetic properties of the follow-up hydrogenation of the thin film are observed via magneto-optic Kerr effect microscopy. The system exhibits strong vertical and lateral antiferromagnetic coupling in the perpendicular component between the areas with and without plasma pretreatment, and asymmetric domain-wall propagation in the plasma-pretreated areas during magnetization reversal. These phenomenon exhibit evident magnetic chirality and can be interpreted with the Ruderman-Kittel-Kasuya-Yosida coupling and the Dzyaloshinskii-Moriya interaction (DMI). The sample processing demonstrated in this study allows easy incorporation of lithography techniques that can define areas with or without DMI to create intricate magnetic patterns on the sample, which provides an avenue towards more sophisticate control of canted spin textures in future spintronic devices., Comment: Supplementary materials available at https://pubs.acs.org/doi/10.1021/acsami.1c23276#notes-1