Advanced Materials
Ultrahigh-Sensitive Broadband Photodetectors Based on Dielectric Shielded MoTe₂/Graphene/SnS₂ p–g–n Junctions
Advanced Materials · 31, 1805656 (2019)
Read original paper
Introduction
The team stacked p-type MoTe₂, graphene and n-type SnS₂ between layers of hexagonal boron nitride. The semiconductors absorb complementary parts of the spectrum, while the junction assists separation of photoexcited charge. At room temperature the device detected illumination at wavelengths spanning 405 to 1,550 nm.
A closer reading
The stack separates two design questions: which photons can be absorbed, and how efficiently the resulting charges reach the electrodes. Read responsivity alongside wavelength, incident power and bias; a peak value at one setting need not hold across the band. The journal frontispiece illustrates the stack, while the measured performance belongs to the paper’s curves.