Mechanic torque induced by chiral phonons: high-throughput calculations and universal force field approach

Chiral phonons, which are induced by the inversion symmetry breaking, are able to carry finite angular momentum. By applying thermal gradient, materials within 65 Sohncke class II and III groups can generate mechanic torque along the same direction with the thermal gradient. Qualifying this torque across a wide range of materials is still blank. We propose to search the materials in Materials Projection database, using DFT calculations, to construct a database containing all the materials with their mechanic torque, as well as angular momentum information. Then, Universal Machine Learning Force Field is employed to try to accelerate this process, where materials will be roughly filtered and only those with large mechanic torque will be remained. In that way, computation cost will be highly reduced and expensive DFT calculations can be effectively used on those materials with large mechanic torque, which are much more preferred.