| Title | The Auger process in multilayer WSe2 crystals |
| Authors | Li, Yuanzheng Shi, Jia Chen, Heyu Wang, Rui Mi, Yang Zhang, Cen Du, Wenna Zhang, Shuai Liu, Zheng Zhang, Qing Qiu, Xiaohui Xu, Haiyang Liu, Weizhen Liu, Yichun Liu, Xinfeng |
| Affiliation | Division of Nanophotonics, CAS Key Laboratory of Standardization and Measurement for Nanotechnology, CAS Center for Excellence in Nanoscience, National Center for Nanoscience and Technology, Beijing, 100190, China Centre for Advanced Optoelectronic Functional Materials Research, Key Laboratory of UV-Emitting Materials and Technology (Northeast Normal University), Ministry of Education, Changchun, 130024, China Center for Programmable Materials, School of Materials Science and Engineering, Nanyang Technological University, Singapore, 639798, Singapore Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing, 100871, China University of Chinese Academy of Sciences, 19 A Yuquan Rd, Shijingshan District, Beijing, 100049, China |
| Issue Date | 2018 |
| Publisher | Nanoscale |
| Citation | Nanoscale. 2018, 10(37), 17585-17592. |
| Abstract | Multilayer WSe2 with a larger optical density of states and absorbance is regarded as a better candidate than its monolayer counterpart for next generation optoelectronic devices, however insight into carrier dynamics is still lacking. Herein, we experimentally observed an anomalous PL quenching with decreasing temperature for multilayer WSe2. At a low temperature (77 K), the Auger processes govern carrier recombination in multilayer WSe2, which are induced by a phonon bottleneck effect and strong photon absorption, and lead to PL quenching. From transient absorption spectroscopy, two distinct Auger processes are observed: a fast one (1-2 ps) and a slow one (>190 ps), which are caused by two different deep midgap defect-levels in WSe2. Based on the Auger recombination model, these two Auger rates are quantitatively estimated at �?.69 (±0.05) × 10-2 and 1.22 (±0.04) × 10-3 cm2 s-1, respectively. Our current observations provide an important supplement for optimizing the optical and electric behaviors in multilayer WSe2 based devices. © 2018 The Royal Society of Chemistry. |
| URI | http://hdl.handle.net/20.500.11897/530521 |
| ISSN | 20403364 |
| DOI | 10.1039/c8nr02567c |
| Indexed | EI |
| Appears in Collections: | 工学院 |
