Science. 1992 Oct 16;258(5081):414-21. doi: 10.1126/science.258.5081.414.
Quantum tunneling, the passage of a microscopic system from one state to another by way of a classically forbidden path, is theoretically possible in the macroscopic world. One can now make direct observations of such macroscopic quantum tunneling in very small magnetic structures. This is possible because of significant advances both in the ability to obtain magnetic systems of almost any desirable size, shape, and composition and in the development of superconducting instrumentation for the detection of extremely weak magnetic signals. As an example, measurements on magnetic horse spleen ferritin proteins with the predictions of quantum tunneling theory are discussed and shown.
量子遂穿，即微观系统通过经典上被禁止的路径从一种状态跃迁到另一种状态，在理论上在宏观世界中也是可能的。现在人们可以在非常小的磁性结构中直接观察到这种宏观量子遂穿。这之所以成为可能，是因为在获得几乎任何所需尺寸、形状和组成的磁性系统的能力以及开发用于检测极弱磁信号的超导仪器方面都取得了重大进展。例如，讨论并展示了对具有量子遂穿理论预测的磁性马脾铁蛋白的测量。
