Synergistic Effects of Plasmonics and Electron Trapping in Graphene Short-Wave Infrared Photodetectors with Ultrahigh Responsivity

Abstract

Graphene's unique electronic and optical properties have made it an attractive material for developing ultrafast short-wave infrared (SWIR) photodetectors. However, the performance of graphene SWIR photodetectors has been limited by the low optical absorption of graphene as well as the ultrashort lifetime of photoinduced carriers. Here, we present two mechanisms to overcome these two shortages and demonstrate a graphene-based SWIR photodetector with high responsivity and fast photoresponse. In particular, a vertical built-in field is employed in the graphene channel for trapping the photoinduced electrons and leaving holes in graphene, which results in prolonged photoinduced carrier lifetime. On the other hand, plasmonic effects were employed to realize photon trapping and enhance the light absorption of graphene. Thanks to the above two mechanisms, the responsivity of this proposed SWIR photodetector is up to a record of 83 A/W at a wavelength of 1.55 μm with a fast rising time of less than 600 ns. This device design concept addresses key challenges for high-performance graphene SWIR photodetectors and is promising for the development of mid/far-infrared optoelectronic applications.

2D Metal Chalcogenides for IR Photodetection

“…And the authors found that ferroelectric‐driven transistor is capable of detecting the NIR wavelength range 900–1550 nm (Figure d), which due to the depletion of dark current and the change of MoS 2 bandgap caused by the external local electrostatic field from the ferroelectric polymer . Recently, surface plasmon resonance (SPR) technology has been widely used in IR detectors due to its unique properties in resonance absorption, subwavelength confinements, and near‐field enhancements . Wang et al have reported the SPR enhanced NIR photodetector using bilayer MoS 2 and asymmetric Au plasmonic structure consisting of nonresonant wires (NRWs) and resonant wires (RWs) .…”

Metallic nanoislands on graphene: a metamaterial for chemical, mechanical, optical, and biological applications

“…66 Other applications in energy conversion include the use of symmetric patterns of gold on graphene for the generation of photocurrent by Halas and others. 3,27,67,68,69,70,71 In these applications, the gold is used to enhance light absorption by localized surface plasmon resonance, and hot carriers are shuttled into the underlying graphene which generates a photocurrent. Radial symmetry of the gold structures is crucial in this application, as it mitigates phonon scattering, which impedes electron transport.…”

“…Similar work exploiting surface plasmon resonance was demonstrated by Etchermeyer and coworkers who showed significant polarization-dependent enhancement of photocurrent with simple patterns of gold lines (Figure 5c, d). 69 Radially symmetric structures, such as gold bowtie antennas fabricated by nanosphere lithography fabricated by Chen and coworkers, 67 have been used to enhance light absorption in the NIR and enhanced photoresponse (Figure 5e, f). The strong wavelength dependence of surface plasmon resonance on geometry allows researchers to adjust parameters lithographically, such as the spacing of nanodisks by Liu and coworkers (Figure 5g), and subsequently control the wavelength of light absorbed (Figure 5h).…”

“…(f) AuBT-Gr substrates have exhibited a highly sensitive time response for photocurrent as shown in (f), which shows great promise in photodetector applications. (e) and (f) reprinted with permission from reference 67 . Copyright 2017, American Chemical Society.…”

Research Progress in Application of 2D Materials in Liquid-Phase Lubrication System

“…Two-dimensional materials, such as boron nitride (BN) and molybdenum disulfide (MoS 2 ), were also discovered subsequently [9]. Given their excellent performance, 2D materials hold great application potential in various fields including microelectronic devices, sensors, catalysts, batteries, biomedicine, and composite materials [10,11,12,13,14,15,16,17,18,19,20,21,22,23]. Scholars found that the phenomenon of superlubricity exists in layered 2D materials, such as MoS 2 and BN [24,25,26,27,28,29], and they experimentally investigated the excellent anti-friction properties of 2D materials [30,31,32,33,34,35,36].…”