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DOE OSTI · 3001933

Robust supermoiré pattern in large-angle single-twist bilayers

Li, Yanxing [Univ. of Texas, Austin, TX (United States)] (ORCID:0009000883096349)·Shi, Chuqiao [Rice Univ., Houston, TX (United States)] (ORCID:0000000163725445)·Zhang, Fan [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000151419782)·Liu, Xiaohui [Univ. of Texas, Austin, TX (United States)]·Xue, Yuan [Univ. of Texas, Austin, TX (United States)]·Ha, Viet-Anh [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000266651274)·Gao, Qiang [Harvard Univ., Cambridge, MA (United States)]·Dong, Chengye [Pennsylvania State Univ., University Park, PA (United States)] (ORCID:0000000185985758)·Lin, Yu-Chuan [Pennsylvania State Univ., University Park, PA (United States); National Yang Ming Chiao Tung Univ., Hsinchu (Taiwan)] (ORCID:0000000349585073)·Holtzman, Luke N. [Columbia Univ., New York, NY (United States)] (ORCID:0009000798987075)·Morales-Durán, Nicolás [Univ. of Texas, Austin, TX (United States); Flatiron Institute, New York, NY (United States)] (ORCID:0000000286553620)·Kim, Hyunsue [Univ. of Texas, Austin, TX (United States)]·Jiang, Yi [Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)] (ORCID:0000000228071324)·Holbrook, Madisen [Columbia Univ., New York, NY (United States)] (ORCID:0000000220193562)·Hone, James [Columbia Univ., New York, NY (United States)] (ORCID:0000000280843301)·Barmak, Katayun [Columbia Univ., New York, NY (United States)] (ORCID:000000030070158X)·Robinson, Joshua A. [Pennsylvania State Univ., University Park, PA (United States)] (ORCID:0000000215137187)·Li, Xiaoqin [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000222793078)·Giustino, Feliciano [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000192931176)·Khalaf, Eslam [Harvard Univ., Cambridge, MA (United States)]·Han, Yimo [Rice Univ., Houston, TX (United States)] (ORCID:0000000305634611)·Shih, Chih-Kang [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000327347023)
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Abstract

Forming long-wavelength moiré superlattices in van der Waals bilayers that have a small-angle twist between the two layers has been a key approach for creating moiré flat bands. However, for small twist angles, strong lattice reconstruction creates domain walls and other forms of disorder in the moiré pattern, posing considerable challenges for engineering such platforms. At large twist angles, the lattices are more rigid, but it is difficult to produce flat bands in shorter-wavelength moiré superlattices. Here, in this study, we introduce an approach for tailoring robust supermoiré structures in bilayers of transition-metal dichalcogenides using only a single twist near a commensurate angle. Structurally, we show the spontaneous formation of a periodic arrangement of three inequivalent commensurate moiré stackings, where the angle deviation from the commensurate angle determines the periodicity. Electronically, we reveal a large set of van Hove singularities that indicate strong band hybridization, leading to flat bands near the valence band maximum. Our study extends the study of the interplay among band topology, quantum geometry and moiré superconductivity to the large twist angle regime.

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Li, Yanxing [Univ. of Texas, Austin, TX (United States)] (ORCID:0009000883096349), Shi, Chuqiao [Rice Univ., Houston, TX (United States)] (ORCID:0000000163725445), Zhang, Fan [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000151419782), Liu, Xiaohui [Univ. of Texas, Austin, TX (United States)], Xue, Yuan [Univ. of Texas, Austin, TX (United States)], Ha, Viet-Anh [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000266651274), Gao, Qiang [Harvard Univ., Cambridge, MA (United States)], Dong, Chengye [Pennsylvania State Univ., University Park, PA (United States)] (ORCID:0000000185985758), Lin, Yu-Chuan [Pennsylvania State Univ., University Park, PA (United States); National Yang Ming Chiao Tung Univ., Hsinchu (Taiwan)] (ORCID:0000000349585073), Holtzman, Luke N. [Columbia Univ., New York, NY (United States)] (ORCID:0009000798987075), Morales-Durán, Nicolás [Univ. of Texas, Austin, TX (United States); Flatiron Institute, New York, NY (United States)] (ORCID:0000000286553620), Kim, Hyunsue [Univ. of Texas, Austin, TX (United States)], Jiang, Yi [Argonne National Laboratory (ANL), Argonne, IL (United States). Advanced Photon Source (APS)] (ORCID:0000000228071324), Holbrook, Madisen [Columbia Univ., New York, NY (United States)] (ORCID:0000000220193562), Hone, James [Columbia Univ., New York, NY (United States)] (ORCID:0000000280843301), Barmak, Katayun [Columbia Univ., New York, NY (United States)] (ORCID:000000030070158X), Robinson, Joshua A. [Pennsylvania State Univ., University Park, PA (United States)] (ORCID:0000000215137187), Li, Xiaoqin [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000222793078), Giustino, Feliciano [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000192931176), Khalaf, Eslam [Harvard Univ., Cambridge, MA (United States)], Han, Yimo [Rice Univ., Houston, TX (United States)] (ORCID:0000000305634611), Shih, Chih-Kang [Univ. of Texas, Austin, TX (United States)] (ORCID:0000000327347023). 2025-05-16. Robust supermoiré pattern in large-angle single-twist bilayers. https://doi.org/10.1038/s41567-025-02914-9

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