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Title: Raman spectroscopy of phonon states in NbTe 4 and TaTe 4 quasi‐one‐dimensional van der Waals crystals
Abstract We report the results of polarization‐dependent Raman spectroscopy of phonon states in single‐crystalline quasi‐one‐dimensional NbTe4and TaTe4van der Waals materials. The measurements were conducted in the wide temperature range from 80 to 560 K. Our results show that although both materials have identical crystal structures and symmetries, there is a drastic difference in the intensity of their Raman spectra. While TaTe4exhibits well‐defined peaks through the examined wavenumber and temperature ranges, NbTe4reveals extremely weak Raman signatures. The measured spectral positions of the phonon peaks agree with the phonon band structure calculated using the density‐functional theory. We offer possible reasons for the intensity differences between the two van der Waals materials. Our results provide insights into the phonon properties of NbTe4and TaTe4van der Waals materials and indicate the potential of Raman spectroscopy for studying charge‐density‐wave quantum condensate phases.  more » « less
Award ID(s):
1921958
PAR ID:
10492223
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Raman Spectroscopy
Volume:
55
Issue:
6
ISSN:
0377-0486
Format(s):
Medium: X Size: p. 695-705
Size(s):
p. 695-705
Sponsoring Org:
National Science Foundation
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