Speeding up the creation of coherent superposition states by shortcut-to-adiabaticity means

We propose protocols of loop stimulated Raman shortcut-to-adiabatic passage (STIRSAP) and modified-STIRSAP to speed up the creation of arbitrary high fidelity coherent superposition states (F similar or equal to 0.999). In loop- and modified-STIRSAP protocols, the nonadiabatic coupling between the dark and bright states can be canceled by an additional microwave pulse and modified pump and Stokes pulses, respectively. As a result of dark state rotation, the creation of preselected coherent superposition states can be achieved beyond the adiabatic limit. Compared with the stimulated Raman adiabatic passage (STIRAP) protocol, the evolution time of the creation of coherent superposition states can be shortened. Our numerical calculations agree well with the theoretical analysis in the partial dressed-state picture. (C) 2020 Elsevier Inc. All rights reserved.