Conflicts of Interest The authors declare no conflicts of interests. Data Availability Statement The data that support the findings of this study are available from the corresponding author upon reasonable request. Supporting Information Filename Description smll75851-sup-0001-SuppMat.pdf89.6 MB Supporting File: smll75851-sup-0001-SuppMat.pdf. References 1, , , et al., “Boosting Classical and Quantum Nonlinear Processes in Ultrathin van der Waals Materials,” Nature Communications 16, no.
