We clarify the symmetry requirements for the emergence of chiral phonons in both 2D square lattices and three-dimensional tetragonal lattices. For two dimensions, the realization of C4 chiral phonons requires the breaking of time-reversal symmetry; while for three dimensions, they can exist on the ...
In monolayer hexagonal lattices, the intravalley and intervalley scattering of electrons can involve chiral phonons at Brillouin-zone center and corners, respectively. At these high-symmetry points, there is a threefold rotational symmetry endowing phonon eigenmodes with a quantized pseudoangular momentum...
Such a non-Abelian CSL can be distinguished by a Z2 symmetry into the two classes: the deconfined and dimer phases. In the deconfined phase, an up-soliton and down-soliton repel each other in real space, and thus up and down solitons appear alternately with the same distances, as ...
Ultrafast phonon diffuse scattering as a tool for observing chiral phonons in monolayer hexagonal latticesBERRY PHASEDYNAMICSAt the 2D limit, hexagonal systems such as monolayer transition metal dichalcogenides (TMDs) and graphene exhibit unique coupled spin and momentum-valley physics (valley pseudospin) ...
Chiral phonons in lattices with C4 symmetry. Phys. Rev. B 2022, 105, 104301. [Google Scholar] [CrossRef] Chen, H.; Wu, W.; Zhu, J.; Gong, W.; Gao, W.; Yang, S.A.; Zhang, L. Chiral Phonons in Chiral Materials. arXiv 2021, arXiv:2109.08872. [Google Scholar] Ishito, K....