Läuchli, AndreasMila, FrédéricPenc, Karlo2019-06-242019-06-242019-06-24200610.1103/PhysRevLett.97.087205https://infoscience.epfl.ch/handle/20.500.14299/158486Using mean-field theory, exact diagonalizations, and SU(3) flavor theory, we have precisely mapped out the phase diagram of the S=1 bilinear-biquadratic Heisenberg model on the triangular lattice in a magnetic field, with emphasis on the quadrupolar phases and their excitations. In particular, we show that ferroquadrupolar order can coexist with short-range helical magnetic order, and that the antiferroquadrupolar phase is characterized by a remarkable 2/3 magnetization plateau, in which one site per triangle retains quadrupolar order while the other two are polarized along the field. Implications for actual S=1 magnets are discussed.text::journal::journal article::research article