2019/04/14 by Lujun Wang, Simon Zihlmann, Andreas Baumgartner +6 · 50 citations
Chemistry · Engineering · Materials Science · Physics and Astronomy · #Advancements in Semiconductor Devices and Circuit Design #Capacitance #Chemistry #Electrode #Graphene #Graphene research and applications #In situ #Materials science #Nanotechnology #Optics #Optoelectronics #Physics #Quantum and electron transport phenomena #Raman spectroscopy #Silicon #Strain (injury) #Strain engineering #Substrate (aquarium) #cond-mat.mes-hall
paper · pdf · open access · doi:10.1021/acs.nanolett.9b01491
published in Nano Letters 19(6), 4097-4102 (American Chemical Society)
arxiv created 2019/04/14 · openalex publication_date 2019/05/22 · arxiv updated 2019/06/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
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.