Broadband high photoresponse from pure monolayer graphene photodetector

Abstract

Graphene has attracted large interest in photonic applications owing to its promising optical properties, especially its ability to absorb light over a broad wavelength range, which has lead to several studies on pure monolayer graphene-based photodetectors. However, the maximum responsivity of these photodetectors is below 10 mA W À 1 , which significantly limits their potential for applications. Here we report high photoresponsivity (with high photoconductive gain) of 8.61 A W À 1 in pure monolayer graphene photodetectors, about three orders of magnitude higher than those reported in the literature, by introducing electron trapping centres and by creating a bandgap in graphene through band structure engineering. In addition, broadband photoresponse with high photoresponsivity from the visible to the mid-infrared is experimentally demonstrated. To the best of our knowledge, this work demonstrates the broadest photoresponse with high photoresponsivity from pure monolayer graphene photodetectors, proving the potential of graphene as a promising material for efficient optoelectronic devices.

Highly Efficient Infrared Photodetection in a Gate‐Controllable Van der Waals Heterojunction with Staggered Bandgap Alignment

“…In addition, the other important optoelectronic parameters,38, 39, 40 such as detectivity and external quantum efficiency, were also extracted from the photodetectors fabricated on the ReS 2 , ReSe 2 , and ReS 2 /ReSe 2 heterojunctions; the plotted data is provided in the Supporting Information chapter (Figure S5, Supporting Information). Finally, for performance comparison of the gate‐controllable ReS 2 /ReSe 2 heterojunction photodetector with other devices, we plotted the photoresponsivity values obtained in this study and previous studies for vdW photodetectors4, 5, 6, 7, 8, 9, 10, 11, 13, 23, 41, 42, 43 in Figure 4k. Our gate‐controllable ReS 2 /ReSe 2 heterojunction photodetector (blue dotted line) exhibited relatively high photoresponsivity values over a broad range of wavelengths, compared to other vdW photodetectors.…”

“…Since the graphene photodetector was first implemented in 2009,1 various van der Waals (vdW) materials, such as graphene,1, 2, 3, 4 transition metal dichalcogenides (TMDs),5, 6, 7, 8, 9, 10, 11, 12 and black phosphorus (BP),13, 14, 15 have been utilized to achieve high‐performance photodetectors with high photoresponsivity and a wide detection range. In the early graphene‐based photodetectors, photodetection in a wide range from ultraviolet to terahertz wavelengths was possible, owing to the zero‐bandgap nature of graphene 16.…”

Ultrafast, Broadband Photodetector Based on MoSe2/Silicon Heterojunction with Vertically Standing Layered Structure Using Graphene as Transparent Electrode

“…They show great potential for broadband, high‐sensitivity, and flexible photodetection due to the large light absorption and ultrathin thickness 34, 38. Although the gapless band structure of graphene offers the capability of ultrawide band detection, the short lifetimes of the photogenerated carriers in graphene (in the ps range) hinder the improvement of photocurrent 36, 39, 40.…”

Monolithic optoelectronic integrated broadband optical receiver with graphene photodetectors

“…As GPDs can respond to optical signals with a wavelength covering all optical communication bands, the GPD-based optical receivers have a chance to serve both short wavelength and long wavelength optical communications [31]. Meanwhile, graphene material with high quality and large area can be obtained with the low-cost chemical vapor deposition (CVD) technology [32].…”