Lattice model parameters for ultracold nonreactive molecules: chaotic scattering and its limitations

摘要

We calculate the parameters of the recently-derived many-channel Hubbardmodel that is predicted to describe ultracold nonreactive molecules in anoptical lattice, going beyond the approximations used in Do\c{c}aj \textit{etal.}~[Phys. Rev. Lett. \textbf{116}, 135301 (2016)]. Although thoseapproximations are expected to capture the qualitative structure of the modelparameters, finer details and quantitative values are less certain. To setexpectations for experiments, whose results depend on the model parameters, wedescribe the approximations' regime of validity and the likelihood thatexperiments will be in this regime, discuss the impact that the failure ofthese approximations would have on the predicted model, and develop theoriesgoing beyond these approximations. Not only is it necessary to know the modelparameters in order to describe experiments, but the connection that weelucidate between these parameters and the underlying assumptions that are usedto derive them will allow molecule experiments to probe new physics. Forexample, transition state theory, which is used across chemistry and chemicalphysics, plays a key role in our determination of lattice parameters, thusconnecting its physical assumptions to highly accurate experimentalinvestigation.