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DOE OSTI · 3010966

Orbital selective band re-normalization induced Lifshitz transition in TiSe 2

Yilmaz, Turgut [Xiamen Univ. Malaysia, Sepeng (Malaysia); Univ. of Connecticut, Storrs, CT (United States)] (ORCID:0000000175710937)·Ng, Yi Sheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)]·Ideta, Shinichiro [Hiroshima Univ. (Japan)]·Shimada, Kenya [Hiroshima Univ. (Japan)] (ORCID:0000000219452352)·Zheng, Jin-Cheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)] (ORCID:0000000262923236)·Wang, Hui-Qiong [Xiamen Univ. Malaysia, Sepeng (Malaysia)]·Rajapitamahuni, Anil [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000330924258)·Kundu, Asish K. [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)]·Vescovo, Elio [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000303503861)
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Abstract

A Lifshitz transition is a sudden change in Fermi surface topology, often linked to quantum phenomena, with major impact on transport and sometimes superconductivity. Here we demonstrate a Lifshitz transition in TiSe 2 using micro–angle-resolved photoemission spectroscopy. At low temperatures an electron pocket appears at the Brillouin-zone center, whereas at higher temperatures spectral weight from a hole-like valence band dominates the Fermi level. Unlike previously reported cases typically driven by rigid band shifts, in TiSe 2 an orbital-selective strong band renormalization induces the crossover near 160 K. This mechanism naturally explains the longstanding resistivity anomaly of TiSe 2 , which peaks around 160 K. Our results clarify its puzzling transport behavior and open avenues to investigate how periodic lattice distortions interact with strong electronic correlations.

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36 MATERIALS SCIENCEPhase transitions and critical phenomenaTwo-dimensional materials

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Yilmaz, Turgut [Xiamen Univ. Malaysia, Sepeng (Malaysia); Univ. of Connecticut, Storrs, CT (United States)] (ORCID:0000000175710937), Ng, Yi Sheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)], Ideta, Shinichiro [Hiroshima Univ. (Japan)], Shimada, Kenya [Hiroshima Univ. (Japan)] (ORCID:0000000219452352), Zheng, Jin-Cheng [Xiamen Univ. Malaysia, Sepeng (Malaysia)] (ORCID:0000000262923236), Wang, Hui-Qiong [Xiamen Univ. Malaysia, Sepeng (Malaysia)], Rajapitamahuni, Anil [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000330924258), Kundu, Asish K. [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)], Vescovo, Elio [Brookhaven National Laboratory (BNL), Upton, NY (United States). National Synchrotron Light Source II (NSLS-II)] (ORCID:0000000303503861). 2025-11-17. Orbital selective band re-normalization induced Lifshitz transition in TiSe 2. https://doi.org/10.1038/s42005-025-02336-2

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36 MATERIALS SCIENCE↗