14. High-quality SnSe2 single crystal: Electronic and thermoelectric properties

Anh-Tuan Pham, Hoa T. Vu, Cheng Chang, Ly T. Trinh, Ji-Eun Lee, Hyejin Ryu, Choongyu Hwang Sung-Kwan Mo, Jungdae Kim, Li-dong Zhao, Anh-Tuan Duong, and Sunglae Cho*

ACS Appl. Energy Mater. 3, 11 (2020) [PDF preprint]

13.  Tunable Kondo resonance at a pristine two-dimensional Dirac semimetal on a Kondo insulator

Jinwoong Hwang, Seungseok Lee, Ji-Eun Lee, Minhee Kang, Hyejin Ryu, Hyunjeong Joo, Jonathan Denlinger, Jae-Hoon Park*, and Choongyu Hwang*

Nano Lett. 20, 7973 (2020) [PDF preprint]

12. A plausible method of preparing the ideal p-n junction interface of a thermoelectric material by surface doping

Ji-Eun Lee, Jinwoong Hwang, Minhee Kang, Hyunjeong Joo, Hyejin Ryu,, Kyoo Kim, Yongsam Kim, Namdong Kim, Anh Tuan Duong, Sunglae Cho, Sung-Kwan Mo, Choongyu Hwang*, and Imjeong Ho-Soon Yang*

Appl. Surf. Sci. 520, 146314 (2020) [PDF reprint]

11.  Controlling the magnetic anisotropy of van der Waals ferromagnet Fe3GeTe2

Se Young Park, Dong Seob Kim, Yu Liu, Jinwoong Hwang, Younghak Kim, Wondong Kim, Jae-Young Kim, Cedomir Petrovic, Choongyu Hwang, Sung-Kwan Mo, Byung-Jun Kim, Byoung-Chul Min, Hyun Cheol Koo, Joonyeon Chang, Chaun Jang*, Jun Woo Choi*, and Hyejin Ryu,*

Nano Lett. 20, 95 (2020) [PDF preprint]

10.  Identifying substitutional oxygen as a prolific point defect in monolayer transition metal dichalcogenides

Sara Barja*, Sivan Refaely-Abramson, Bruno Schuler, Diana Y. Qiu, Artem Pulkin, Sebastian Wickenburg, Hyejin Ryu,, Miguel M. Ugeda, Christoph Kastl, Christopher Chen, Choongyu Hwang, Adam Schwartzberg, Shaul Aloni, Sung-Kwan Mo, D. Frank Ogletree, Michael F. Crommie, Oleg V. Yazyev, Steven G. Louie*, Jeffrey B. Neaton*, Alexander Weber-Bargioni*

Nat. Commun. 10, 3382 (2019) [PDF preprint]

9. Anisotropic Dirac Fermions in BaMnBi2 and BaZnBi2

Hyejin Ryu†*, Se Young Park†, Lijun Li, Weijun Ren, Jeffrey Neaton, Cedomir Petrovic, Choongyu Hwang, and Sung-Kwan Mo* (†: equal contribution)

Sci. Rep. 8, 15322 (2018) [PDF reprint]

8.  Emergence of Kondo resonance in graphene intercalated with cerium

Jinwoong Hwang†, Kyoo Kim†, Hyejin Ryu,, Jingul Kim, Ji-Eun Lee, Sooran Kim, Minhee Kang, Byeong-Gyu Park, Alessandra Lanzara, Jinwook Chung, Sung-Kwan Mo, Jonathan Denlinger, Byung Il Min, and Choongyu Hwang* (†: equal contribution)

Nano Lett. 18, 3661 (2018)  [PDF reprint]

7.  Persistent charge-density-wave order in single-layer TaSe2

Hyejin Ryu*, Yi Chen, Heejung Kim, Hsin-Zon Tsai, Shujie Tang, Juan Jiang, Franklin Liou, Salman Kahn, Caihong Jia, Arash A. Omrani, Ji Hoon Shim, Zahid Hussain, Zhi-Xun Shen, Kyoo Kim, Byung Il Min, Choongyu Hwang, Michael F. Crommie, and Sung-Kwan Mo*

Nano Lett. 18, 689 (2018) [PDF reprint]

6. Electronic structure of monolayer 1T'-MoTe2 grown by molecular beam epitaxy

Shujie Tang, Chaofan Zhang, Chunjing Jia, Hyejin Ryu, Choongyu Hwang, Zhi Liu, Makoto Hashimoto, Donghui Lu, Thomas P. Devereaux, Zhi-Xun Shen*, and Sung-Kwan Mo*

APL Mater. 6, 026601 (2018) [PDF reprint]

5.  Temperature-dependent electron-electron interaction in graphene on SrTiO3

Hyejin Ryu†, Jinwoong Hwang†, Debin Wang, Ankit S. Disa, Jonathan Denlinger, Yuegang Zhang, Sung-Kwan Mo*, Choongyu Hwang*, and Alessandra Lanzara (†: equal contribution)

Nano Lett. 17, 5914 (2017) [PDF reprint]

4. ARPES study of the epitaxially grown topological crystalline insulator SnTe(111) 

Yi Zhang, Zhongkai Liu, Bo Zhou, Yeongkwan Kim, Lexian Yang, Hyejin Ryu, Choongyu Hwang, Yulin Chen, Zahid Hussain, Zhi-Xun Shen, and Sung-Kwan Mo*

J. Electron Spectrosc. Relat. Phenom. 219, 35 (2017) [PDF reprint]

3. Hole doping, hybridization gaps, and electronic correlation in graphene on a platinum substrate

Jinwoong Hwang†, Hwihyeon Hwang†, Min-Jeong Kim, Hyejin Ryu, Ji-Eun Lee, Qin Zhou*, Sung-Kwan Mo, Jaekwang Lee, Alessandra Lanzara, and Choongyu Hwang* (†: equal contribution)

Nanoscale 9, 11498 (2017) [PDF reprint]

2.  Quantum spin Hall state in monolayer 1T'-WTe2

Shujie Tang, Chaofan Zhang, Dillon Wong, Zahra Pedramrazi, Hsin-Zon Tsai, Chunjin Jia, Hyejin Ryu, Salman Kahn, Juan Jiang, Hao Yan, Makoto Hashimoto, Donghui Lu, Robert G. Moore, Chancuk Hwang, Choongyu Hwang, Yulin Chen, Zhi Liu, Xiaoming Xie, Thomas P. Devereaux, Michael F. Crommie, Sung-Kwan Mo*, and Zhi-Xun Shen*

Nature Phys. 13, 683 (2017) [PDF reprint]

1.  Electronic Structure, Surface Doping, and Optical Response in Epitaxial WSe2 Thin Films 

Yi Zhang*, Miguel M. Ugeda, Chenhao Jin, Su-Fei Shi, Aaron J. Bradley, Ana Martin-Recio, Hyejin Ryu, Jonghwan Kim, Shujie Tang, YeongKwan Kim, Bo Zhou, Choongyu Hwang, Yulin Chen, Feng Wang, Michael F. Crommie, Zahid Hussain, Zhi-Xun Shen, and Sung-Kwan Mo*

Nano Lett. 16, 2485 (2016) [PDF reprint]