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arXiv · 1701.09013

Electronic structure of transferred graphene/h-BN van der Waals heterostructures with nonzero stacking angles by nano-ARPES

Eryin Wang·Guorui Chen·Guoliang Wan·Xiaobo Lu·Chaoyu Chen·Jose Avila·Alexei V Fedorov·Guangyu Zhang·Maria C Asensio·Yuanbo Zhang·Shuyun Zhou
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Abstract

In van der Waals heterostructures, the periodic potential from the Moir\'e superlattice can be used as a control knob to modulate the electronic structure of the constituent materials. Here we present a nanoscale angle-resolved photoemission spectroscopy (Nano-ARPES) study of transferred graphene/h-BN heterostructures with two different stacking angles of 2.4{\deg} and 4.3{\deg} respectively. Our measurements reveal six replicas of graphene Dirac cones at the superlattice Brillouin zone (SBZ) centers. The size of the SBZ and its relative rotation angle to the graphene BZ are in good agreement with Moir\'e superlattice period extracted from atomic force microscopy (AFM) measurements. Comparison to epitaxial graphene/h-BN with 0{\deg} stacking angles suggests that the interaction between graphene and h-BN decreases with increasing stacking angle.

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Eryin Wang, Guorui Chen, Guoliang Wan, Xiaobo Lu, Chaoyu Chen, Jose Avila, Alexei V Fedorov, Guangyu Zhang, Maria C Asensio, Yuanbo Zhang, Shuyun Zhou. 2017-01-31. Electronic structure of transferred graphene/h-BN van der Waals heterostructures with nonzero stacking angles by nano-ARPES. https://doi.org/10.1088/0953-8984/28/44/444002

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