  To date, orbital angular momentum (OAM) and optical frequency combs (OFCs)
are two distinct fields of research without any association. Herein, we
generated OFCs with an OAM on each comb line by applying electro-optic phase
modulation to the OAM beam. We verified that the OAM characteristic of the
sidebands is consistent with that of the pump light. Our study bridges two
distinct research fields OFCs and OAM opening the door to various fundamental
research avenues and applications, including large-capacity optical
communications, high-security optical encryption, multi-dimensional photon
entanglement, and synthetic dimensions.
