A gate induced insulating behavior at zero magnetic field is observed in a high mobility suspended monolayer graphene near the charge neutrality point. The graphene device initially cleaned by a current annealing technique was undergone a thermo-pressure cycle to allow short range impurities to be adsorbed directly on the ultra clean graphene surface. The adsorption process generated a strong temperature and electric field dependent behavior on the conductance of the graphene device. The conductance around the neutrality point is observed to be reduced from around e2/h at 30 K to ∼0.01e2/h at 20 mK. A direct transition from insulator to quantum Hall conductor within ≈0.4T accompanied by broken-symmetry-induced ν=0,±1 plateaux confirms the presence of intervalley scatterers.
@article{arxiv.2006.11797,
title = {Strong localization in a suspended monolayer graphene by intervalley scattering},
author = {Cenk Yanik and Vahid Sazgari and Abdulkadir Canatar and Yaser Vaheb and Ismet I. Kaya},
journal= {arXiv preprint arXiv:2006.11797},
year = {2021}
}