  Interacting quantum systems in the chaotic domain are at the core of various
ongoing studies of many-body physics, ranging from the scrambling of quantum
information to the onset of thermalization. We propose a minimum model for
chaos that can be experimentally realized with cold atoms trapped in
one-dimensional multi-well potentials. We explore the emergence of chaos as the
number of particles is increased, starting with as few as two, and as the
number of wells is increased, ranging from a double well to a multi-well
Kronig-Penney-like system. In this way, we illuminate the narrow boundary
between integrability and chaos in a highly tunable few-body system. We show
that the competition between the particle interactions and the periodic
structure of the confining potential reveals subtle indications of quantum
chaos for 3 particles, while for 4 particles stronger signatures are seen. The
analysis is performed for bosonic particles and could also be extended to
distinguishable fermions.
