AI 中文总结
该研究揭示半连续Au薄膜与CrO2粉末压实体中电学网络为条件依赖子集，提出链路启用与重新加权两种可转换重构模式，表明几何连通性不足以解释强不均匀导体输运。
AI 中文摘要
尽管半连续Au薄膜和压实CrO2粉末在形貌、维度和微观输运机制上存在根本差异，但它们收敛于一个共同的网络层面原理：电学相关的网络是物理接触网络中依赖于条件的子集。在接近几何渗流阈值的Au薄膜中，增大偏压可逆地将低温响应从具有负磁电阻的激活最近邻跳跃转变为具有正磁电阻的弱局域化类行为，这与固定岛状网络中更广泛的电子参与一致。在CrO2粉末压实体中，磁场主要改变现有晶粒间界面的自旋相关电阻，从而重新排列相互竞争的电流路径；温度和测量电流还能额外扩展或缩减活跃网络。Cohn定理为这两种情况提供了一个简洁的灵敏度原理：局部电阻变化对测量响应的影响与受影响链路上承载的电流成正比。该比较识别出两种极限但可相互转换的重构模式——链路启用和链路重新加权——并揭示了为何仅凭几何连通性不足以解释强不均匀导体中的输运。
英文摘要
Despite fundamental differences in morphology, dimensionality, and microscopic transport, semicontinuous Au films and compacted CrO2 powders converge on a common network-level principle: the electrically relevant network is a condition-dependent subset of the physical contact network. In Au films near the geometrical percolation threshold, increasing bias reversibly shifts the low-temperature response from activated nearest-neighbour hopping with negative magnetoresistance to a weak-localization-like regime with positive magnetoresistance, consistent with broader electronic participation of the fixed island network. In CrO2 powder compacts, magnetic field mainly changes the spin-dependent resistances of existing intergranular junctions and thereby reorders competing current paths; temperature and measuring current can additionally expand or deplete the active network. Cohn's theorem provides a compact sensitivity principle for both cases: local resistance changes influence the measured response in proportion to the current carried by the affected links. The comparison identifies two limiting but interconvertible modes of reconfiguration - link enabling and link reweighting - and shows why geometrical connectivity alone is insufficient for interpreting transport in strongly inhomogeneous conductors.
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