Doçaj, AndrisWall, Michael L.Mukherjee, RickHazzard, Kaden R.A.2017-05-032017-05-032016Doçaj, Andris, Wall, Michael L., Mukherjee, Rick, et al.. "Ultracold Nonreactive Molecules in an Optical Lattice: Connecting Chemistry to Many-Body Physics." <i>Physical Review Letters,</i> 116, no. 13 (2016) American Physical Society: https://doi.org/10.1103/PhysRevLett.116.135301.https://hdl.handle.net/1911/94132We derive effective lattice models for ultracold bosonic or fermionic nonreactive molecules (NRMs) in an optical lattice, analogous to the Hubbard model that describes ultracold atoms in a lattice. In stark contrast to the Hubbard model, which is commonly assumed to accurately describe NRMs, we find that the single on-site interaction parameter U is replaced by a multichannel interaction, whose properties we elucidate. Because this arises from complex short-range collisional physics, it requires no dipolar interactions and thus occurs even in the absence of an electric field or for homonuclear molecules. We find a crossover between coherent few-channel models and fully incoherent single-channel models as the lattice depth is increased. We show that the effective model parameters can be determined in lattice modulation experiments, which, consequently, measure molecular collision dynamics with a vastly sharper energy resolution than experiments in a free-space ultracold gas.engArticle is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use.Journal articlehttps://doi.org/10.1103/PhysRevLett.116.135301