Effective Hamiltonian and dynamics of the dipole-octupole pyrochlore Ce2Zr2O7

Recent neutron scattering measurements on the three-dimensional pyrochlore magnet Ce2Zr2O7 have revealed compelling signatures of quantum spin liquid behavior. This strongly spin-orbit coupled system is composed of interacting ground state doublets of cerium (J=5/2 mJ = ± 3/2), with dipole - octupole character with local Ising anisotropy. While it can be modelled as interacting effective pseudospin-1/2 degrees of freedom, the strengths of the interaction parameters of its spin Hamiltonian remain unknown. To address this issue, we perform extensive fits of this model to experimentally measured magnetization profiles (along [100] and [111]) and specific heat measurements (in zero and finite field) computed with the finite temperature Lanczos method. We assess the importance of quantum mechanical effects and explore the possibility of the existence of spin ice physics in this material. Using the obtained parameters, we perform classical Monte Carlo, Gaussian approximation, and Landau-Lifshitz dynamical calculations and compare them to the experimentally observed static and dynamic spin structure factor.