Exploring Novel Phenomena in 2D Quantum Transistors

2D quantum materials have recently gained significant popularity in the field of research, owing to the continuous discovery of numerous novel phenomena over the years. In this presentation, I will be sharing the phenomena that we have uncovered in the past decade. This encompasses not only quantum tunneling behavior but also the development of transistors based on innovative mechanisms. For example, in both the stacking of transition metal dichalcogenides (TMD) [1] and the lateral growth of two types of TMD materials [2], we have observed resonant tunneling behavior involving discrete quantum states. Leveraging this tunneling mechanism, we have achieved high-frequency operation (up to 64GHz) in graphene-based hot electron transistors [3]. Furthermore, based on theoretical simulations, we have predicted that negative differential resistance can be influenced by defects in monolayer 2D materials. Accordingly, we have experimentally validated this theoretical prediction in monolayer MoS2 and clay graphite through simple fabrication processes, controlling the appropriate number of defects [4-5]. If time allowed, new results on ferroelectricity in bilayer 3R MoS2 [6] also will be presented in this talk. 

Keywords – MoS2, 2D materials, transition metal dichalcogenides, resonant tunnelling, negative differential resistance


References
Linh-Nam Nguyen, Yann-Wen Lan*, Jyun-Hong Chen, Yuan-Liang Chung, Kuei-Shu Chang-Liao, Lain-Jong Li, and Chii-Dong Chen*. “Resonant tunneling through discrete quantum states in stacked atomic-layered MoS2” Nano Letters, 14(5), pp 2381-2386, 2014. 
Che-Yu Lin, Xiaodan Zhu, Shin-Hung Tsai, Shiao-Po Tsai, Sidong Lei, Yumeng Shi, Lain-Jong Li, Shyh-Jer Huang, Wen-Fa Wu, Wen-Kuan Yeh, Yan-Kuin Su, Kang L. Wang and Yann-Wen Lan* “Atomic-Monolayer Two-Dimensional Lateral Quasi-Heterojunction Bipolar Transistors with Resonant Tunneling Phenomenon” ACS Nano 2017, 11 (11), 11015-11023. 
Bor-Wei Liang, Wen-Hao Chang, Hung-Yu Lin, Po-Chun Chen, Yi-Tang Zhang, Kristan Bryan Simbulan, Kai-Shin Li, Jyun-Hong Chen, Chieh-Hsiung Kuan* and Yann-Wen Lan*. High-Frequency Graphene Base Hot-Electron Transistor. ACS Nano 2021, 15, 6756-6764 (18 March 2021). 
Shu-Ting Yang, Tilo H. Yang, Chun-I Lu, Wen-Hao Chang, Kristan Bryan Simbulan, Yann-Wen Lan*. Room Temperature Negative Differential Resistance in Clay-Graphite Paper Transistors. Carbon 2021, 176, 440-445 (accepted 08 Feb 2021) 
Wen-Hao Chang, Chun-I Lu, Tilo H. Yang, Shu-Ting Yang, Kristan Bryan Simbulan, Chih-Pin Lin, Shang-Hsien Hsieh, Jyun-Hong Chen, Kai-Shin Li, Chia-Hao Chen, Tuo-Hung Hou, Ting-Hua Lu, and Yann-Wen Lan*. Defect-engineered room temperature negative differential resistance in monolayer MoS2 transistors. Nanoscale Horizons, DOI: 10.1039/d2nh00396a, 17th October 2022 
[6] Tilo H. Yang…., Yann-Wen Lan*, Ferroelectric transistors based on shear-transformation-mediated rhombohedral-stacked molybdenum disulfide. Nature electronics, accepted in October 2023.