2020/12/31 by Shuang-Xing Zhu, Chen Zhang, Qi-Yi Wu +24 · 21 citations
Materials Science · Physics and Astronomy · #2D Materials and Applications #Anharmonicity #Atmospheric temperature range #Atomic physics #Condensed matter physics #Coupling (piping) #Materials science #Nuclear magnetic resonance #Phonon #Photoemission spectroscopy #Physics #Quantum Dots Synthesis And Properties #Quantum mechanics #Quasiparticle #Spectroscopy #Superconductivity #Thermodynamics #Topological Materials and Phenomena #X-ray photoelectron spectroscopy #cond-mat.mtrl-sci
paper · pdf · doi:10.1103/physrevb.103.115108
published in Physical review. B./Physical review. B 103(11) (American Physical Society) · 7 pages, 4 figures
openalex publication_date 2021/03/04 · arxiv created 2021/03/06 · arxiv updated 2021/03/09 · openalex created_date 2021/03/15 · openalex updated_date 2026/08/05
High-resolution angle-resolved photoemission spectroscopy and ultrafast optical pump-probe spectroscopy were used to study semimetallic 1T\ensuremath-TiTe2 quasiparticle dispersion and dynamics. A kink and a flat band, having the same energy scale and temperature-dependent behaviors along the \mathrm\ensuremathΓ\text\ensuremath-M direction, were detected. Both manifested at low temperatures but blurred as temperature increased. The kink was formed by an electron-phonon coupling. And the localized flat band might be closely related to an electron-phonon coupling. Ultrafast optical spectroscopy identified multiple distinct time scales in the 10--300 K range. Quantitative analysis of the fastest decay process evidenced a significant lifetime temperature dependence at high temperatures, while this starts to change slowly below \ensuremath∼100 K where an anomalous Hall coefficient occurred. At low temperature, a coherent A1g phonon mode with a frequency of \ensuremath∼4.36 THz was extracted. Frequency temperature dependence suggests that phonon hardening occurs as temperature falls and anharmonic effects can explain it. Frequency fluence dependence indicates that the phonons soften as fluence increases.