Chemical doping can be used to control the charge-carrier polarity and concentration in two-dimensional van der Waals materials. However, conventional methods based on substitutional doping or surface functionalization result in the degradation of electrical mobility due to structural disorder, and the maximum doping density is set by the solubility limit of dopants. Here we show that a reversible laser-assisted chlorination process can be used to create high doping concentrations (above 3 × 10¹³ cm⁻²) in graphene monolayers with minimal drops in mobility. The approach uses two lasers—with distinct photon energies and geometric configurations—that are designed for chlorination and subsequent chlorine removal, allowing highly doped patterns to be written and erased without damaging the graphene. To illustrate the capabilities of our approach, we use it to create rewritable photoactive junctions for graphene-based photodetectors.

化学掺杂可用于控制二维范德华材料中的电荷载流子极性和浓度。然而，基于替代掺杂或表面功能化的常规方法会由于结构无序导致电迁移率下降，并且最大掺杂密度由掺杂剂的溶解度限制决定。在这里，我们展示了可逆的激光辅助氯化工艺可用于产生高掺杂浓度（高于 3 × 10 ¹³  cm ^-2) 在石墨烯单层中，迁移率下降最小。该方法使用两种激光——具有不同的光子能量和几何结构——设计用于氯化和随后的氯去除，允许在不损坏石墨烯的情况下写入和擦除高度掺杂的图案。为了说明我们方法的能力，我们使用它为基于石墨烯的光电探测器创建可重写的光敏结。