Chiral phonon mediated high-temperature superconductivity

Breaking down the traditional perception on phonons which are achiral, the existence of a chiral phonon carrying angular momentum provides possible ways to couple electrons, photons, spins, magnons, and excitons, etc. We theoretically proposed an electron-chiral phonon interaction with a two-phonon process, in contrast to a conventional electron-phonon interaction, and a kind of effective Hubbard interaction through exchanging two chiral phonons is proposed. Taking a two-dimensional diatomic honeycomb lattice as an example, we found this repulsive Hubbard interaction mediated by chiral phonons induces unconventional and high-temperature superconductivity. Moreover, the numerical calculations show an inverse isotope effect which is consistent with experimental observations in high-${T}_{c}$ superconductors. Our finding on an electron-chiral phonon and the associated Cooper pair provides a path to understand the high-${T}_{c}$ superconductivity.