  We present a tensor-network method for strong-coupling QCD with staggered
quarks at nonzero chemical potential. After integrating out the gauge fields at
infinite coupling, the partition function can be written as a full contraction
of a tensor network consisting of coupled local numeric and Grassmann tensors.
To evaluate the partition function and to compute observables, we develop a
Grassmann higher-order tensor renormalization group method, specifically
tailored for this model. We apply the method to the two-dimensional case and
validate it by comparing results for the partition function, the chiral
condensate and the baryon density with exact analytical expressions on small
lattices up to volumes of $4\times4$. For larger two-dimensional volumes, we
present tensor results for the chiral condensate as a function of the mass and
volume, and observe that the chiral symmetry is not broken dynamically in two
dimensions. Furthermore, our results for the number density as a function of
the chemical potential hint at a first-order phase transition. Finally, we
present some preliminary tensor results for three-dimensional strong-coupling
QCD.
