Ultrasensitive Near-Infrared Photodetectors Based on a Graphene–MoTe₂–Graphene Vertical van der Waals Heterostructure

-Si) voltage. We compared the responsivities of thin and thick flakes and found that the responsivity had a strong dependence on the thickness. The heterostructure has promising applications in future novel optoelectronic devices, enabling next-generation high-responsivity, high-speed, flexible, and transparent NIR devices.