Highly sensitive infrared polarized photodetector enabled by out-of-plane PSN architecture composing of p-MoTe2, semimetal-MoTe2 and n-SnSe2

Abstract

Leveraging the unique physical properties, two-dimensional (2D) materials have circumvented the disadvantages of conventional epitaxial semiconductors and held great promise for potential optoelectronic applications. So far, two main detector architectures including photodiode based on a van der Waals P-N junction or Schottky junction and phototransistor based on individual 2D materials or hybrids have been well developed. However, a trade-off between responsivity and speed always exists in those technologies thus hindering the overall performance improvement. Here, we propose a new device concept by sandwiching the 2D anisotropic semimetal between p-type and n-type semiconductors in the out-of-plane direction, called PSN architecture, realizing the improvement of each parameter including broad spectral coverage, fast speed, high sensitivity, power-free and polarization-sensitive. We stack the p-type 2H-MoTe 2 , Weyl semimetal 1T-MoTe 2 and n-type SnSe 2 layer-by-layer constructing vertical sandwich structure where the top and bottom layers contribute to the internal built-in electric field, the intermediate layer can facilitate the exciton dissociation and act as infrared polarized light sensitizers. As a result, this PSN device exhibits broadband photo-response from 405 to 1,550 nm without external bias supply. At optical communication band (1,310 nm), operating at self-driven mode and room temperature, the responsivity and detectivity can reach up to 64.2 mA•W -1 and 2.2×10 11 Jones, respectively, along with fast speed on the order of millisecond. Moreover, the device simultaneously exhibits exceptional detection capability for infrared polarized light, demonstrating the anisotropic photocurrent ratio of 1.55 at 1,310 nm and 2.02 at 1,550 nm, which is attributed to the strong in-plane optical anisotropy of middle 1T-MoTe 2 layer. This work develops a new photodetector scheme with novel PSN architecture toward broadband, self-power, polarized light sensing and imaging modules.

Engineering the Polarization Sensitivity in All‐2D Photodetectors Composed of Semimetal MoTe2 and Semiconductor WS2

“…Polarization-sensitive photodetectors have been attracting increasing attention due to their intrinsic polarization sensitivity for a large range of applications such as polarization Particularly, 2D semimetal tellurides with narrow bandgap and low-symmetric crystalline structure, like 1T-MoTe 2 , [17,18] 1T-WTe 2 , [19] and TaIrTe 4 , [20,21] have played dominant roles in near-and mid-wave infrared polarization-sensitive photodetector. Moreover, the stacking of the desired anisotropic 2D materials can construct various heterojunctions to broaden their application due to the lack of dangling bonds at the surface, which can enable the integration with the arbitrary substrate without the lattice matching constraints.…”

Dielectric Contrast Tailoring for Polarized Photosensitivity toward Multiplexing Optical Communications and Dynamic Encrypt Technology

“…In a commercial scheme, a detection component and a polarizer are conjointly used, which, however, suffers from large volume. To implement compact monolithic integration, alternative channels with intrinsic anisotropic atomic arrangements, including black phosphorus, InSe, 1T-MoTe 2 , T d -WTe 2 , ReSe 2 , PdSe 2 , PbSnS 2 , PdPS, InSiTe 3 , and TaIrTe 4 , have been explored. Insufficiently, these materials suffer from poor stability, exorbitant cost, or sophisticated synthesis techniques.…”

Doping Engineering in the MoS2/SnSe2 Heterostructure toward High‐Rejection‐Ratio Solar‐Blind UV Photodetection

“…The band structure of Nb-doped MoS 2 is shown in Moreover, the highest photoresponsivity is obtained in the SBUV band. Compared with other heterostructures formed by typical TMDs and group-IV metal chalcogenides reported previously, [9,[41][42][43][44][45][46][47] band alignment design of heterostructure and doping engineering are effective methods to achieve SBUV photoelectric detection. More detailed comparisons of the performance parameters of the photodetectors based on the heterostructures shown in Figure 3d are listed in Table 1.…”