MENGKUN LIU
Associate Professor
Physics and Astronomy
mengkun.liu@stonybrook.edu | (631)-632-8175, Physics B-105
Research Group Website

Biography
Mengkun Liu earned his PhD from Boston University, where he worked with Prof. Richard D. Averitt (now in UCSD). He later joined Prof. D. N. Basov's lab at UC San Diego (now at Columbia) and was appointed as an assistant professor at Stony Brook University in 2015. He currently holds a joint appointment at Brookhaven National Laboratory and was promoted to associate professor at Stony Brook University in 2020.

Research Statement
Liu's Ultrafast & Near-field Infrared Laboratory (UNI-Lab) explores the future of materials science using advanced infrared and THz near-field microscopy and nano-Fourier transform IR spectroscopy. Their nanoscale imaging and manipulation of light-matter interactions boasts a spatial resolution over 1000 times higher than conventional optics. The lab studies complex materials like transition metal oxides, low-dimensional Dirac/Weyl microstructures, superconductors, and multiferroics by accessing the native length and time scales of electron and lattice motion and monitoring energy excitations, unlocking the mysteries of Mott physics and other many body effects and bringing closer to practical applications.

Recent Publication Hightlights

Nano-Imaging of Landau-Phonon Polaritons in Dirac Heterostructures
Lukas Wehmeier, Suheng Xu, Rafael A. Mayer, Brian Vermilyea, Makoto Tsuneto, Michael Dapolito, Rui Pu, Zengyi Du, Xinzhong Chen, Wenjun Zheng, Ran Jing, Zijian Zhou, Kenji Watanabe, Takashi Taniguchi, Adrian Gozar, Qiang Li, Alexey B. Kuzmenko, G. Lawrence Carr, Xu Du, Michael M. Fogler, D.N. Basov, Mengkun Liu, Science Advance, accepted.

Electronic interactions in Dirac fluids visualized by nano-terahertz spacetime mapping
Suheng Xu, Yutao Li, Rocco A Vitalone, Ran Jing, Aaron J Sternbach, Shuai Zhang, Julian Ingham, Milan Delor, James McIver, Matthew Yankowitz, Raquel Queiroz, Andrew J Millis, Michael M Fogler, Cory R Dean, James Hone, Mengkun Liu, DN Basov, Science Advance, accepted.

Ultrabroadband Terahertz Near-Field Nanospectroscopy with a HgCdTe Detector
Wehmeier, Lukas; Liu, Mengkun; Park, Suji; Jang, Houk; Homes, Christopher; Carr, G. Lawrence, ACS photonics, 10, 12, 4329–4339 (2023).

Infrared Nano-Imaging of Dirac Magnetoexcitons in Graphene.
Michael Dapolito, Makoto Tsuneto, Wenjun Zheng, Lukas Wehmeier, Suheng Xu, Xinzhong Chen, Jiacheng Sun, Zengyi Du, Yinming Shao, Ran Jing, Shuai Zhang, Adrien Bercher, Yinan Dong, Dorri Halbertal, Vibhu Ravindran, Zijian Zhou, Adrian Gozar, GL Carr, Qiang Li, Alexey Kuzmenko, Michael Fogler, Dmitri Basov, Xu Du, Mengkun Liu. Nature Nanotechnology, 18, 1409–1415 (2023).

Machine Learning for Optical Scanning Probe Nanoscopy, Xinzhong Chen, Suheng Xu, Sara Shabani, Yueqi Zhao, Matthew Fu, Andrew J Millis, Michael M Fogler, Abhay N Pasupathy, Mengkun Liu*, DN Basov*, Advanced Materials, 2109171 (2022).

Probing subwavelength in-plane anisotropy with antenna-assisted infrared nano-spectroscopy, Ziheng Yao, Xinzhong Chen, Lukas Wehmeier, Yinming Shao, Zimeng Zeng, Fanwei Liu, Alexander S. Mcleod, Stephanie N. Gilbert Corder, Makoto Tsuneto, Suheng Xu, Wu Shi, Zihang Wang, Wenjun Zheng, Hans A. Bechtel, G. L. Carr, Michael C. Martin, Alex Zettl, D. N. Basov, Xi Chen, Lukas M. Eng, Susanne C. Kehr, Mengkun Liu*, Nature Communications 12, 2649 (2021).

Moiré Engineering of Electronic Phenomena in Correlated Oxides, Xinzhong Chen, Xiaodong Fan, Lin Li*, Nan Zhang, Zhijing Niu, Tengfei Guo, Suheng Xu, Han Xu, Dongli Wang, Huayang Zhang, A. S. McLeod, Zhenlin Luo, Qingyou Lu, Andrew J. Millis, D. N. Basov*, Mengkun Liu*, Changgan Zeng*, Nature Physics 16, 631–635 (2020).

THz near-field imaging of extreme subwavelength metal structures, Xinzhong Chen, Xiao Liu, Xiangdong Guo, Shu Chen, Hai Hu, Elizaveta Nikulina, Ziheng Yao, Hans A. Bechtel, Michael C. Martin, G. L. Carr, Qing Dai*, Songlin Zhuang, Qing Hu, Yiming Zhu*, Rainer Hillenbrand, Mengkun Liu*, ACS Photonics 7, 687 (2020).

Chiral terahertz wave emission from the Weyl semimetal TaAs, Y. Gao, Y. Qin, Sahal Kaushik, Evan J. Philip, Y. P. Liu, Y. L. Su, X. Chen, Z. Li, H. Weng, Dmitri E. Kharzeev*, M. K. Liu*, J. Qi*, Nature Communications 11, 720 (2020).

Nano-resolved current-induced insulator-metal transition in the Mott insulator Ca₂RuO₄, Jiawei Zhang, Alexander. S. McLeod, Qiang Han, Xinzhong Chen, Hans A. Bechtel, Ziheng Yao, S. N. Gilbert Corder, Thomas Ciavatti, Hu (Tiger) Tao, Meigan Aronson, G. L. Carr, Michael C. Martin, Chanchal Sow, Shingo Yonezawa, Fumihiko Nakamura, Ichiro Terasaki, D. N. Basov, Andrew J. Millis*, Yoshiteru Maeno*, Mengkun Liu*, Physical Review X 9, 011032 (2019).