Complete transfer of populations from a single state to a preselected superposition of states using piecewise adiabatic passage: Theory

We develop a method for executing robust and selective transfer of populations between a single level and preselected superpositions of energy eigenstates. Viewed in the frequency domain, our method amounts to executing a series of simultaneous adiabatic passages into each component of the target superposition state. Viewed in the time domain, the method works by accumulating the wave function of the target wave packet as it revisits the transition region, in what amounts to an extension of the piecewise adiabatic passage technique [ E. A. Shapiro et al. Phys. Rev. Lett. 99 033002 (2007)] to the multistate regime. The viability of the method is verified by performing numerical tests for the Na₂ molecule.