Yan B.,Peking University |
Yan B.,Collaborative Innovation Center on Quantum Matter |
Han Q.,Peking University |
Han Q.,Collaborative Innovation Center on Quantum Matter |
And 10 more authors.
Physical Review B - Condensed Matter and Materials Physics | Year: 2016
We study the intervalley scattering in defected graphene by low-temperature transport measurements. The scattering rate is strongly suppressed when defects are charged. This finding highlights "screening" of the short-range part of a potential by the long-range part. Experiments on calcium-adsorbed graphene confirm the role of a long-range Coulomb potential. This effect is applicable to other multivalley systems, provided that the charge state of a defect can be electrically tuned. Our result provides a means to electrically control valley relaxation and has important implications in valley dynamics in valleytronic materials. © 2016 American Physical Society.