Quantum manifestations of Nekhoroshev stability

•Basic quantum manifestations of classical Nekhoroshev theory are studied.•A simple anisochronous convex system with two degrees of freedom is proposed.•Zones are uncovered in the joint expectation value spectrum of quantized actions.•The width of the zones is given by the Nekhoroshev resonant normal forms.

We uncover quantum manifestations of classical Nekhoroshev theory of resonant dynamics using a simple quantum system of two coupled angular momenta with conserved equal magnitudes which corresponds to a perturbed classical integrable anisochronous Hamiltonian system.