|
|
|
Charge-imbalance-induced second harmonic generation in twisted graphene |
| Ronghui Luo(罗荣辉)1, Shiyang Liu(刘诗洋)1, Xiao Dong(董校)1, Jianguo Tian(田建国)1, and Zhibo Liu(刘智波)1,2,† |
1 The Key Laboratory of Weak Light Nonlinear Photonics, Ministry of Education, School of Physics and Teda Applied Physics Institute, Nankai University, Tianjin 300071, China;
2 The Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China |
|
|
|
|
Abstract Twist-and-stack engineering provides a programmable degree of freedom for nonlinear optics in two-dimensional materials, yet in a homostructure whose constituents have no second harmonic generation (SHG), how interlayer coupling grants and tunes second-order response remains unclear. Here, we use twisted monolayer-bilayer graphene ($t(1+2)$LG) and combine microscopic SHG spectroscopy with first-principles differential charge-density analysis to establish a unified ``permission-and-resonance'' mechanism. Interlayer coupling creates an interlayer charge imbalance within the AB-stacked bilayer, breaking inversion symmetry and thereby permitting an in-plane electric-dipole response. At the same time, the twist angle steers van Hove singularities in the band structure to achieve two-photon resonance, which markedly amplifies the susceptibility $\chi^{(2)}$. Experimentally, at $\theta =13.5^\circ $, we obtain $\chi^{(2)}=279.4$ pm/V, evidencing a highly efficient second-order response. These results identify SHG as a sensitive probe of interlayer coupling and charge redistribution in homostructure van der Waals systems.
|
Received: 08 December 2025
Revised: 26 December 2025
Accepted manuscript online: 08 January 2026
|
|
PACS:
|
42.65.Ky
|
(Frequency conversion; harmonic generation, including higher-order harmonic generation)
|
| |
78.67.-n
|
(Optical properties of low-dimensional, mesoscopic, and nanoscale materials and structures)
|
|
| Fund: Project supported by the National Natural Science Foundation of China (Grant Nos. 12574339, 12574457, and 12174207) and Tianjin Science and Technology Project (Grant No. 24ZXZSSS00120). |
Corresponding Authors:
Zhibo Liu
E-mail: liuzb@nankai.edu.cn
|
Cite this article:
Ronghui Luo(罗荣辉), Shiyang Liu(刘诗洋), Xiao Dong(董校), Jianguo Tian(田建国), and Zhibo Liu(刘智波) Charge-imbalance-induced second harmonic generation in twisted graphene 2026 Chin. Phys. B 35 034201
|
[1] Lu X, Stepanov P, YangW, Xie M, AamirMA, Das I, Urgell C,Watanabe K, Taniguchi T, Zhang G, Bachtold A, MacDonald A H and Efetov D K 2019 Nature 574 653
[2] Stepanov P, Das I, Lu X, Fahimniya A,Watanabe K, Taniguchi T, Koppens F H L, Lischner J, Levitov L and Efetov D K 2020 Nature 583 375
[3] Saito Y, Ge J,Watanabe K, Taniguchi T and Young A F 2020 Nat. Phys. 16 926
[4] Cao Y, Fatemi V, Demir A, Fang S, Tomarken S L, Luo J Y, Sanchez- Yamagishi J D, Watanabe K, Taniguchi T, Kaxiras E, Ashoori R C and Jarillo-Herrero P 2018 Nature 556 80
[5] Alexeev E M, Ruiz-Tijerina D A, Danovich M, Hamer M J, Terry D J, Nayak P K, Ahn S, Pak S, Lee J, Sohn J I, Molas M R, Koperski M, Watanabe K, Taniguchi T, Novoselov K S, Gorbachev R V, Shin H S, Fal’ko V I and Tartakovskii A I 2019 Nature 567 81
[6] Zhao B J, Zhao J L and Gan X T 2024 Chin. Phys. Lett. 41 104201
[7] Chen H, Li S Q, Wu Y, Bao X, Lei Z, Liu H, Xie Y, Gao J, Chen Y and Yan X 2025 Chin. Phys. B 34 084206
[8] Malard L M, Alencar T V, Barboza A P M, Mak K F and De Paula A M 2013 Phys. Rev. B 87 201401
[9] Ribeiro-Soares J, Janisch C, Liu Z, Elias A L, Dresselhaus M S, Terrones M, Cançado L G and Jorio A 2015 2D Mater. 2 045015
[10] Song Y, Tian R, Yang J, Yin R, Zhao J and Gan X 2018 Adv. Optical Mater. 6 1701334
[11] Jia X, Xu B, Luo J, Liu N, Wang Y, Zheng B, Xu W and Liu K 2025 Chin. Phys. B 34 074205
[12] Hsu W T, Zhao Z A, Li L J, Chen C H, Chiu M H, Chang P S, Chou Y C and Chang W H 2014 ACS Nano 8 2951
[13] Jiang X, Kang L and Huang B 2022 Phys. Rev. B 105 045415
[14] Yuan Y, Liu P, Wu H, Chen H, Zheng W, Peng G, Zhu Z, Zhu M, Dai J, Qin S and Novoselov K S 2023 ACS Nano 17 17897
[15] Zhang M, Han N, Zhang J, Wang J, Chen X, Zhao J and Gan X 2023 Sci. Adv. 9 eadf4571
[16] Wang J, Zhang M, Han N, Luo Z D, Chen X, Liu Y, Zhao J and Gan X 2023 Adv. Optical Mater. 11 2202495
[17] Yang F, SongW, Meng F, Luo F, Lou S, Lin S, Gong Z, Cao J, Barnard E S, Chan E, Yang L and Yao J 2020 Matter 3 1361
[18] Song G, Hong H, Ma C, Hao H, Yan S, Zhang Y, Liu K, Tong L and Zhang J 2025 J. Am. Chem. Soc. 147 473
[19] Kim K, Yankowitz M, Fallahazad B, Kang S, Movva H C P, Huang S, Larentis S, Corbet C M, Taniguchi T, Watanabe K, Banerjee S K, LeRoy B J and Tutuc E 2016 Nano Lett. 16 1989
[20] Kresse G and Furthmüller J 1996 Phys. Rev. B 54 11169
[21] Perdew J P, Burke K and Ernzerhof M 1996 Phys. Rev. Lett. 77 3865
[22] Kresse G and Joubert D 1999 Phys. Rev. B 59 1758
[23] Grimme S, Antony J, Ehrlich S and Krieg H 2010 J. Chem. Phys. 132 154104
[24] Shan Y, Li Y, Huang D, Tong Q, Yao W, Liu W T and Wu S 2018 Sci. Adv. 4 eaat0074
[25] Liu W T, Wu S W, Schuck P J, Salmeron M, Shen Y R and Wang F 2010 Phys. Rev. B 82 081408
[26] Carozo V, Almeida C M, Fragneaud B, Bedê P M, Moutinho M V O, Ribeiro-Soares J, Andrade N F, Souza Filho A G, Matos M J S, Wang B, Terrones M, Capaz R B, Jorio A, Achete C A and Cançado L G 2013 Phys. Rev. B 88 085401
[27] Dean J J and Van Driel H M 2009 Appl. Phys. Lett. 95 261910
[28] Vela A, Moutinho M V O, Culchac F J, Venezuela P and Capaz R B 2018 Phys. Rev. B 98 155135 |
| No Suggested Reading articles found! |
|
|
Viewed |
|
|
|
Full text
|
|
|
|
|
Abstract
|
|
|
|
|
Cited |
|
|
|
|
Altmetric
|
|
blogs
Facebook pages
Wikipedia page
Google+ users
|
Online attention
Altmetric calculates a score based on the online attention an article receives. Each coloured thread in the circle represents a different type of online attention. The number in the centre is the Altmetric score. Social media and mainstream news media are the main sources that calculate the score. Reference managers such as Mendeley are also tracked but do not contribute to the score. Older articles often score higher because they have had more time to get noticed. To account for this, Altmetric has included the context data for other articles of a similar age.
View more on Altmetrics
|
|
|
