Email: phyweets@nus.edu.sg
Office: S13-02-03
Tel: +65 6516 6362
Current Research
My research interests are in the atomic scale studies of the growth and interface properties of surfaces and interfaces, 2D materials and heterointerfaces, and 2D devices. Some recent projects include 2D heterointerfaces, and on-surface synthesis of 2D molecular networks. My Surface Science Lab (SSL) has expertise in STM/STS, ncAFM, XPS/UPS, MBE as well as ARPES, XAS, XMCD at the Singapore Synchrotron Light Source (SSLS).
Figure. Structural characterization of the MoSe2-CrSe2 lateral heterostructures. a, STM image of the MoSe2-CrSe2 lateral heterostructure with a continuous MTB linear defect crossing through the interface (VS = −1.0 V, It = 3 pA). b, The corresponding ball-and-stick model of the lateral heterostructure with a MTB line defect. c, High-resolution STM image of the atomically sharp interface with 3 × 3 moiré pattern in the MoSe2 region (VS = −0.4 V, It = 0.6 nA). d,e, Constant-height nc-AFM images of the MoSe2-CrSe2 interfaces taken at the Se-edge and Mo-edge of MoSe2 nanoribbon with partly overlaid structure models, respectively. The scanning areas are labelled by the purple and black dashed squares in a, respectively (Tip height z = −360 pm relative to the height at the setpoint 1.3 V, 10 pA). f, DFT simulated STM and constant-height nc-AFM images with the corresponding structure model.
Selected Publications
- D Wang, Z Wang, W Liu, Arramel, S Zhong, YP Feng, KP Loh, ATS Wee, “Real‐Space Investigation of the Multiple Halogen Bonds by Ultrahigh‐Resolution Scanning Probe Microscopy”, Small 18 (28), 2202368 (2022).
- Q Guo, XZ Qi, L Zhang, M Gao, S Hu, W Zhou, W Zang, X Zhao, J Wang, B Yan, M Xu, Y-K Wu, G Eda, Z Xiao, SA Yang, H Gou, YP Feng, G-C Guo, W Zhou, X-F Ren, C-W Qiu, SJ Pennycook, ATS Wee; “Ultrathin quantum light source with van der Waals NbOCl2 crystal”, Nature 613 (7942), 53-59 (2023).
- J Gou, H Bai, X Zhang, YL Huang, S Duan, A Ariando, SA Yang, L Chen, Y Lu, ATS Wee; “Two-dimensional ferroelectricity in a single-element bismuth monolayer”, Nature 617 67–72 (2023).
- L Cai, T Gao, ATS Wee, “Topology selectivity of a conformationally flexible precursor through selenium doping”. Nature Communications 15 (1), 3235(2024).
- M Liu, J Gou, Z Liu, Z Chen, Y Ye, J Xu, X Xu, D Zhong, G Eda, ATS Wee, “Phase-selective in-plane heteroepitaxial growth of H-phase CrSe2”, Nature Communications 15 (1), 1765 (2024).
- R Chua, J Henke, S Saha, Y Huang, J Gou, X He, T Das, J van Wezel, A Soumyanarayanan, ATS Wee, “Coexisting Charge-Ordered States with Distinct Driving Mechanisms in Monolayer VSe2”, ACS Nano 16 (1), 783-791 (2021).
- D Wang, Z Wang, S Wu, Arramel, X Yin, CS Tang, YP Feng, J Wu, ATS Wee, “Realizing Two-Dimensional Supramolecular Arrays of a Spin Molecule via Halogen Bonding”, ACS Nanoscience Au 2 (4), 333-340 (2022).
- Q Liang, Z Chen, Q Zhang, ATS Wee, “Pentagonal 2D Transition Metal Dichalcogenides: PdSe2 and Beyond”, Advanced Functional Materials 32 (38), 2203555 (2022).
- CS Tang, S Zeng, J Wu, S Chen, MA Naradipa, D Song, MV Milošević, Ping Yang, Caozheng Diao, Jun Zhou, Stephen J Pennycook, Mark BH Breese, Chuanbing Cai, Thirumalai Venkatesan, Ariando Ariando, Ming Yang, Andrew TS Wee, Xinmao Yin, “Detection of two-dimensional small polarons at oxide interfaces by optical spectroscopy”,Applied Physics Reviews 10 (3) 031406 (2023).
- Dingguan Wang, Tobias Haposan, Jinwei Fan, Arramel, Andrew TS Wee, “Recent Progress of Imaging Chemical Bonds by Scanning Probe Microscopy: A Review”, ACS Nano, 18 (45), 30919-30942 (2024).
Affiliations & Links
- Class of ’62 Professor
- Academician, APAM (Asia-Pacific Academy of Materials)
- Personal Webpage