Structural superlubricity is a fascinating tribological phenomenon, in which the lateral interactions between two incommensurate contacting surfaces are effectively cancelled resulting in ultralow sliding friction. Here we report the experimental realization of robust superlubricity in microscale monocrystalline heterojunctions, which constitutes an important step towards the macroscopic scale-up of superlubricity. The results for interfaces between graphite and hexagonal boron nitride clearly demonstrate that structural superlubricity persists even when the aligned contact sustains external loads under ambient conditions. The observed frictional anisotropy in the heterojunctions is found to be orders of magnitude smaller than that measured for their homogeneous counterparts. Atomistic simulations reveal that the underlying frictional mechanisms in the two cases originate from completely different dynamical regimes. Our results are expected to be of a general nature and should be applicable to other van der Waals heterostructures.

结构的超润滑性是一种引人入胜的摩擦学现象，其中两个不相称的接触面之间的横向相互作用被有效地消除，从而产生了超低的滑动摩擦。在这里，我们报告了在微尺度单晶异质结中鲁棒超润滑性的实验实现，这是朝着宏观上扩大超润滑性迈出的重要一步。石墨和六方氮化硼之间的界面结果清楚地表明，即使对准的触点在环境条件下承受外部载荷，结构超润滑性仍然存在。发现在异质结中观察到的摩擦各向异性比在同类异质结中测得的摩擦各向异性小几个数量级。原子模拟显示，这两种情况下的潜在摩擦机制源自完全不同的动力学机制。预期我们的结果是一般性的，应适用于其他范德华异质结构。