  We numerically study amorphous analogues of a two-dimensional photonic Chern
insulator. The amorphous lattices consist of gyromagnetic rods that break
time-reversal symmetry, with the lattice sites generated by a close-packing
algorithm. The level of short-range order is adjustable, and there is no
long-range order. The topologically nontrivial gaps of the photonic Chern
insulator are found to persist into the amorphous regime, so long as there is
sufficient short-range order. Strongly nonreciprocal robust transmission occurs
via edge states, which are shown to propagate ballistically despite the absence
of long-range order, and to be exponentially localized along the lattice edge.
Interestingly, there is an enhancement of nonreciprocal transmission even at
very low levels of short-range order, where there are no discernable spectral
gaps.
