Cascaded frequency conversion via invariant engineering

Abstract Based on the Lewis-Riesenfeld (LR) invariant based inverse engineering for Shortcuts to adiabaticity (STA), we propose a cascaded frequency conversion technique. The technique maintains the same initial and final states as stimulated Raman adiabatic passage (STIRAP) but does not follow an adiabatic evolution during the intermediate processes. The results of numerical simulations show that the technique transfers the eigenstates from the initial state to the final state by designing an adiabatic evolutionary path, which is free to choose the length of the crystal within the crystal laser-induced damage threshold (LIDT), thus realizing a rapid adiabatic cascaded frequency conversion process with robustness under certain temperature variations and signal-laser wavelength variations.