Twisting or sliding two-dimensional crystals with respect to each other gives rise to moiré patterns determined by the difference in their periodicities. Such lattice mismatches can exist for several reasons: differences between the intrinsic lattice constants of the two layers, as is the case for graphene on BN¹; rotations between the two lattices, as is the case for twisted bilayer graphene²; and strains between two identical layers in a bilayer³. Moiré patterns are responsible for a number of new electronic phenomena observed in recent years in van der Waals heterostructures, including the observation of superlattice Dirac points for graphene on BN¹, collective electronic phases in twisted bilayers and twisted double bilayers^4,5,6,7,8, and trapping of excitons in the moiré potential^9,10,11,12. An open question is whether we can use moiré potentials to achieve strong trapping potentials for electrons. Here, we report a technique to achieve deep, deterministic trapping potentials via strain-based moiré engineering in van der Waals materials. We use strain engineering to create on-demand soliton networks in transition metal dichalcogenides. Intersecting solitons form a honeycomb-like network resulting from the three-fold symmetry of the adhesion potential between layers. The vertices of this network occur in bound pairs with different interlayer stacking arrangements. One vertex of the pair is found to be an efficient trap for electrons, displaying two states that are deeply confined within the semiconductor gap and have a spatial extent of 2 nm. Soliton networks thus provide a path to engineer deeply confined states with a strain-dependent tunable spatial separation, without the necessity of introducing chemical defects into the host materials.

相对于彼此扭曲或滑动的二维晶体，​​会产生由其周期性差异确定的莫尔图案。这种晶格失配可能由于以下几个原因而存在：两层的固有晶格常数之间的差异，例如BN ¹上的石墨烯的情况；在两个晶格之间的旋转，如扭曲的双层石墨烯^2的情况；双层^3中两个相同层之间的应变。莫尔图案是近年来在范德华异质结构中观察到的许多新电子现象的原因，包括观察BN ¹上石墨烯的超晶格狄拉克点，扭曲双层和扭曲双层中的集体电子相^4,5,6,7,8和激子在莫尔势中的^{俘获9,10,11,12}。一个悬而未决的问题是，我们是否可以利用莫尔电位来实现强的电子俘获势。在这里，我们报告了一种技术，该技术通过在范德华斯材料中基于应变的莫尔工程实现深层次的确定性诱捕潜力。我们使用应变工程在过渡金属二卤化硅中创建按需孤子网络。相交的孤子形成蜂窝状网络，这是由于层之间的粘附电位的三重对称性所致。该网络的顶点以绑定对的形式出现，并具有不同的层间堆叠安排。发现该对中的一个顶点是电子的有效陷阱，显示出两个状态，它们被深深地限制在半导体间隙内，并且具有2 nm的空间范围。