Recently, adiabatic passage phenomena discovered in atomic and molecular physics, such as the stimulated Raman adiabatic passage (STIRAP) [ 1 ], have been proposed for controlling photonic tunneling. Concepts such as quantum interference, electromagnetically induced transparency, trapped states, and adiabatic passage have thus entered the photonic community (see, e.g., [ 2 , 3 , 4 , 5 ]). Experimental demonstrations of robust light transfer among evanescently coupled optical waveguid...