Tunable superlattice in graphene to control the number of Dirac points.

نویسندگان

  • Sudipta Dubey
  • Vibhor Singh
  • Ajay K Bhat
  • Pritesh Parikh
  • Sameer Grover
  • Rajdeep Sensarma
  • Vikram Tripathi
  • K Sengupta
  • Mandar M Deshmukh
چکیده

Superlattice in graphene generates extra Dirac points in the band structure and their number depends on the superlattice potential strength. Here, we have created a lateral superlattice in a graphene device with a tunable barrier height using a combination of two gates. In this Letter, we demonstrate the use of lateral superlattice to modify the band structure of graphene leading to the emergence of new Dirac cones. This controlled modification of the band structure persists up to 100 K.

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عنوان ژورنال:
  • Nano letters

دوره 13 9  شماره 

صفحات  -

تاریخ انتشار 2013