Excuse the simpleton question:

> When creating these TBG samples, we used to literally tear the graphene in half, to get accurate relative alignment of the two halves. It was very clever, but it imparts a huge amount of strain to the two layers, generally of order 0.1-0.3%.

Does "it" mean the mechanical tearing of the crystal imparts the strain? or instead is it the newly introduced surface boundary (in 1D) that is imparting strain?

[I ask because long ago I was familiar with some of the crazy surface physics that would happen in IV-IV and III-V systems, and just wondering what effects the 1D termination of the 2D lattice might cause.]