Van der Waals (vdW) heterostructures of 2D atomically thin layered materials (2DLMs) provide a unique platform for constructing optoelectronic devices by staking 2D atomic sheets with unprecedented functionality and performance. A particular advantage of these vdW heterostructures is the energy band engineering of 2DLMs to achieve interlayer excitons through type‐II band alignment, enabling spectral range exceeding the cutoff wavelengths of the individual atomic sheets in the 2DLM. Herein, the high performance of GaTe/InSe vdW heterostructures device is reported. Unexpectedly, this GaTe/InSe vdWs p–n junction exhibits extraordinary detectivity in a new shortwave infrared (SWIR) spectrum, which is forbidden by the respective bandgap limits for the constituent GaTe (bandgap of ≈1.70 eV in both the bulk and monolayer) and InSe (bandgap of ≈1.20–1.80 eV depending on thickness reduction from bulk to monolayer). Specifically, the uncooled SWIR detectivity is up to ≈1014Jones at 1064 nm and ≈1012Jones at 1550 nm, respectively. This result indicates that the 2DLM vdW heterostructures with type‐II band alignment produce an interlayer exciton transition, and this advantage can offer a viable strategy for devising high‐performance optoelectronics in SWIR or even longer wavelengths beyond the individual limitations of the bandgaps and heteroepitaxy of the constituent atomic layers.
High-speed optoelectronics is central to many important developments in the communication, computing, sensing, imaging, and autonomous vehicle industries. With a sharp rise of attention on energy efficiency, researchers have proposed and demonstrated innovative materials, high-speed devices, and components integrated on a single platform that exhibit ultralow power consumption and ultrawide bandwidth. Recently reported material growth and device fabrication techniques offer the potential for high-density integration of optoelectronics close to the capability and cost of conventional electronics. A tremendous synergy can be attained by integrating multiple materials with superior properties on the same chip using heterogeneous integration, heteroepitaxy, nano-heteroepitaxy, and other co-packaging strategies within the complementary metal oxide semiconductor (CMOS) ecosystem. This issue of
- NSF-PAR ID:
- 10369766
- Publisher / Repository:
- Cambridge University Press (CUP)
- Date Published:
- Journal Name:
- MRS Bulletin
- Volume:
- 47
- Issue:
- 5
- ISSN:
- 0883-7694
- Page Range / eLocation ID:
- p. 475-484
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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