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Recently a new research field of quasi-one-dimensional (1D) van der Waals quantummaterials has emerged from earlier work on low-dimensional systems [1-2]. The quasi-1D van der Waalsmaterials have 1D motifs in their crystal structure [1]. Many of these materials reveal strongly correlatedphenomena such as charge density waves (CDW) [1-2]. The CDW phase is a periodic modulation of theelectronic charge density, accompanied by distortions in the underlying crystal lattice. Potential uses for CDWmaterials include memory storage and oscillators [3]. Raman spectroscopy can identify the CDW transitions todifferent phases via the appearance of phonon peaks due to emerging superstructure or the disappearance ofcertain peaks due to the loss of translation symmetry in the crystal lattice [3]. In this presentation, we report theresults of the angle and temperature-dependent Raman scattering spectroscopy investigation of themechanically exfoliated nanowires of the quasi-1D Nb van der Waals material. It is known that Nb forms in atetragonal crystal structure with space group 124 (P4/mcc). Recently, this material attracted attention as aCDW material with multiple phase transitions, some of them, possibly, near room temperature. Littleinformation is known on the Raman characteristics of this material. Our Raman data for different polarizationangles show strong anisotropy in the response depending on the crystal direction. The most pronouncedRaman peaks reveal strong temperature dependence. The results of the measurements will be compared withthe theoretical predictions. Our data is important for further investigation of this quasi-1D CDW material forpossible applications in phase-change memory and reconfigurable devices. A.A.B. acknowledges the support of the Vannevar Bush Faculty Fellowship (VBFF) from the Office of NavalResearch (ONR) contract N00014-21-1-2947 “One-Dimensional Quantum Materials” and the National ScienceFoundation (NSF) program Designing Materials to Revolutionize and Engineer our Future (DMREF) via aproject DMR-1921958 “Data-Driven Discovery of Synthesis Pathways and Distinguishing ElectronicPhenomena of 1D van der Waals Bonded Solids”. A. D. and S. K. acknowledge support through the MaterialGenome Initiative funding allocated to the National Institute of Standards and Technology. [1] A. A. Balandin, F. Kargar, T. T. Salguero, and R. Lake, “One-dimensional van der Waals quantummaterials", Mater. Today, 55, 74 (2022). [2] A. A. Balandin, R. K. Lake, and T. T. Salguero, "One-dimensional van der Waals materials - Advent of a newresearch field" Appl. Phys. Lett., 121, 040401 (2022). [3] A. A. Balandin, S. V. Zaitzev-Zotov, and G. Grüner, "Charge-density-wave quantum materials and devices—New developments and future prospects", Appl. Phys. Lett., 119, 170401 (2021). [4] R. Samnakay, et al., “Zone-folded phonons and the charge-density-wave transition in 1T-TaSe2 thin films, Nano Lett., 15, 2965 (2015). 

Abstract Body: Recently a new research field of quasi-one-dimensional (1D) van der Waals quantummaterials has emerged from earlier work on low-dimensional systems [1-2]. The quasi-1D van der Waalsmaterials have 1D motifs in their crystal structure [1]. Many of these materials reveal strongly correlatedphenomena such as charge density waves (CDW) [1-2]. The CDW phase is a periodic modulation of theelectronic charge density, accompanied by distortions in the underlying crystal lattice. Potential uses for CDWmaterials include memory storage and oscillators [3]. Raman spectroscopy can identify the CDW transitions todifferent phases via the appearance of phonon peaks due to emerging superstructure or the disappearance ofcertain peaks due to the loss of translation symmetry in the crystal lattice [3]. In this presentation, we report theresults of the angle and temperature-dependent Raman scattering spectroscopy investigation of themechanically exfoliated nanowires of the quasi-1D Nb van der Waals material. It is known that Nb forms in atetragonal crystal structure with space group 124 (P4/mcc). Recently, this material attracted attention as aCDW material with multiple phase transitions, some of them, possibly, near room temperature. Littleinformation is known on the Raman characteristics of this material. Our Raman data for different polarizationangles show strong anisotropy in the response depending on the crystal direction. The most pronouncedRaman peaks reveal strong temperature dependence. The results of the measurements will be compared withthe theoretical predictions. Our data is important for further investigation of this quasi-1D CDW material forpossible applications in phase-change memory and reconfigurable devices. A.A.B. acknowledges the support of the Vannevar Bush Faculty Fellowship (VBFF) from the Office of NavalResearch (ONR) contract N00014-21-1-2947 “One-Dimensional Quantum Materials” and the National ScienceFoundation (NSF) program Designing Materials to Revolutionize and Engineer our Future (DMREF) via aproject DMR-1921958 “Data-Driven Discovery of Synthesis Pathways and Distinguishing ElectronicPhenomena of 1D van der Waals Bonded Solids”. A. D. and S. K. acknowledge support through the MaterialGenome Initiative funding allocated to the National Institute of Standards and Technology. [1] A. A. Balandin, F. Kargar, T. T. Salguero, and R. Lake, “One-dimensional van der Waals quantummaterials", Mater. Today, 55, 74 (2022). [2] A. A. Balandin, R. K. Lake, and T. T. Salguero, "One-dimensional van der Waals materials - Advent of a newresearch field" Appl. Phys. Lett., 121, 040401 (2022). [3] A. A. Balandin, S. V. Zaitzev-Zotov, and G. Grüner, "Charge-density-wave quantum materials and devices—New developments and future prospects", Appl. Phys. Lett., 119, 170401 (2021). [4] R. Samnakay, et al., “Zone-folded phonons and the charge-density-wave transition in 1T-TaSe2 thin films,” Nano Lett., 15, 2965 (2015).