In Situ Strain Tuning in hBN-Encapsulated Graphene Electronic Devices.

Wang L; Zihlmann S; Baumgartner A; Overbeck J; Watanabe K; Taniguchi T; Makk P; Schönenberger C

doi:10.1021/acs.nanolett.9b01491

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Journal article

In Situ Strain Tuning in hBN-Encapsulated Graphene Electronic Devices.

Wang L Empa , Swiss Federal Laboratories for Materials Science and Technology , Überlandstrasse 129 , CH-8600 , Dübendorf , Switzerland.
Zihlmann S National Institute for Material Science , 1-1 Namiki , Tsukuba 305-0044 , Japan.
Baumgartner A National Institute for Material Science , 1-1 Namiki , Tsukuba 305-0044 , Japan.
Overbeck J Department of Physics , Budapest University of Technology and Economics and Nanoelectronics Momentum Research Group of the Hungarian Academy of Sciences , Budafoki ut 8 , 1111 Budapest , Hungary.
Watanabe K
Taniguchi T
Makk P
Schönenberger C

2019-05-24

Published in:

Nano letters. - 2019

English Using a simple setup to bend a flexible substrate, we demonstrate deterministic and reproducible in situ strain tuning of graphene electronic devices. Central to this method is the full hBN encapsulation of graphene, which preserves the exceptional quality of pristine graphene for transport experiments. In addition, the on-substrate approach allows one to exploit strain effects in the full range of possible sample geometries and at the same time guarantees that changes in the gate capacitance remain negligible during the deformation process. We use Raman spectroscopy to spatially map the strain magnitude in devices with two different geometries and demonstrate the possibility to engineer a strain gradient, which is relevant for accessing the valley degree of freedom with pseudomagnetic fields. Comparing the transport characteristics of a suspended device with those of an on-substrate device, we demonstrate that our new approach does not suffer from the ambiguities encountered in suspended devices.

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