Introducing uniaxial local strain to graphene encapsulated with hBN

Strain engineering is a promising method for controlling electron transport in graphene. From our previous experimental result, we found that the observation of gap formation by lattice strain requires large spatial variation of strain and long mean free path of charge carriers. For satisfying above requirements, we developed new method for introducing lattice strain to graphene. In this method, we suspended graphene on hBN films with hole which was formed by reactive ion etching. And then, we pushed suspended part of graphene by hBN pole for introduction of lattice strain to graphene. From micro Raman spectroscopy, we confirmed the spatial variation of lattice strain depending on the geometry of hBN films. And we measured the modulation of transport properties.