  Experimental data shows that both ionization charge and scintillation light
in LAr depend on the deposited energy density ($dE/dx$) and electric field
($\mathcal{E}$). Moreover, free ionization charge and scintillation light are
anticorrelated, complementary at a given ($dE/dx$, $\mathcal{E}$) pair. We
present LArQL, a phenomenological model that provides the anticorrelation
between light and charge and its dependence on the deposited energy as well as
on the electric field applied. It modifies the Birks' charge model considering
the contribution from the escape electrons at null and low electric fields, and
reconciles with Birks' model prediction at higher fields. Deviations from
current Birks' model are observed for LArTPCs operating at low $\mathcal{E}$
and for heavily ionizing particles. The LArQL model presents a satisfactory
description at $dE/dx$ and field ranges for interacting particles in LArTPCs
and fits well the available data. Improvements via data sets compilation and
global fits are also interesting features of the model.
