Comment on 'Spin-Momentum-Locked Edge Mode for Topological Vortex Lasing, Phys. Rev. Lett. vol. 125, 013903 (2020)'

We present a comment on "Spin-Momentum-Locked Edge Mode for Topological Vortex Lasing, Phys. Rev. Lett. vol. 125, 013903 (2020)"(hereafter the Letter).In the Letter, Yang et al. reported on an elegant topological vortex laser and proposed that the near-field spin and OAM of the topological edge mode lasing have a one-to-one far-field radiation correspondence. The near-field information is based on frequency dispersions of the topological edge modes, without supporting measurements and/or computer simulations. Unfortunately, their frequency dispersions shown in Fig. 1(c) (see also Fig. S6 and Eqs. (5.3) and (5.4) in Supplemental Material) are wrong. As the result, the mode assignment of the main mode |-2,+> investigated in the Letter is mistaken, which should be |2,+>. This spoils the one-to-one correspondence claimed in the Letter.