Low-Frequency Raman Study of Large-Area Twisted Bilayers of WS2 Stacked by an Etchant-Free Transfer Method

• DOI: 10.1021/acsami.3c14708
• Publication Date: 2024-01-03T11:14:00Z
• Authors: Manpreet Boora; Yu-Chuan Lin; Chen Chen; Nicholas Trainor; Joshua A. Robinson; Joan M. Redwing; Jae Yong Suh

Monolayer transition metal dichalcogenides have strong intracovalent bonding. When stacked in multilayers, however, weak van der Waals interactions dominate interlayer mechanical coupling and, thus, influence their lattice vibrations. This study presents the frequency evolution of phonons twisted WS2 bilayers, highly subject to twist angle. The angle between layers is controlled modulate spacing layers, which, turn, affects that probed by Raman spectroscopy. shifts high-frequency E2g1 (Γ) and A1g phonon modes separations are dependent on angle, reflecting correlation In this work, we fabricated large-area, bilayer with a clean interface angles. Polarized spectroscopy identified new modes, which were not previously reported, depending appearance breathing spectra provides evidence structures. We confirm can alter exciton trion dynamics bilayers as indicated photoluminescence peak shift. These large-area samples practical applications optoelectronic device fabrication twistronics.