We develop a control framework for broadband population transfer in ensembles of $n$-level quantum systems with time-dependent energy levels and time-varying dispersion across ensemble members. Ensemble inhomogeneity is modeled through time-varying dispersion functions that capture Hamiltonian variations across the ensemble. The control field is chosen so that the $n$-level dynamics reduces to an effective retained subspace for the target transition that is dynamically decoupled from the rest of the space in the reduced description. By careful phase design, ensemble dispersion appears only as a global phase in the final state, thereby ensuring uniform population transfer across all ensemble members. We apply the proposed control framework to quadrupolar nuclei under magic-angle spinning, where rotor motion naturally generates both explicit time dependence of the nominal energy levels and time-dependent dispersion across crystallites. Numerical simulations in this setting demonstrate uniform broadband population transfer and illustrate the framework in a physically meaningful multilevel ensemble system with explicitly time-varying inhomogeneity.

Close

PrevNext

View figure in article

• Quantum control
• Quantum engineering
• Quantum protocols
• Quantum state transfer