  A periodically driven quantum system with avoided-level crossing experiences
both non-adiabatic transitions and wave-function phase changes. These result in
coherent interference fringes in the system's occupation probabilities. For
qubits, with repelling energy levels, such interference, named after
Landau-Zener-Stuckelberg-Majorana, displays arc-shaped resonance lines. We
demonstrate that in the case of a multi-level system with an avoided-level
crossing of the two lower levels, the shape of the resonances can change from
convex arcs to concave heart-shaped and harp-shaped resonance lines. In this
way, the shape of such resonance fringes is defined by the whole spectrum,
providing insight on the slow-frequency system spectroscopy. As a particular
example, we consider this for valley-orbit silicon quantum dots.
