Experimental implementation of assisted quantum adiabatic passage in a   single spin
  Quantum adiabatic passages can be greatly accelerated by a suitable control field, called a counter-diabatic field, which varies during the scan through resonance. Here, we implement this technique on the electron spin of a single nitrogen-vacancy center in diamond. We demonstrate two versions of this scheme. The first follows closely the procedure originally proposed by Demirplak and Rice (J. Phys. Chem. A 107, 9937 (2003)). In the second scheme, we use a control field whose amplitude is constant, but its phase varies with time. This version, which we call the rapid-scan approach, allows an even faster passage through resonance and therefore makes it applicable also for systems with shorter decoherence times. 
Jingfu Zhang, Jeong Hyun Shim, Ingo Niemeyer, T. Taniguchi, T. Teraji,   H. Abe, S. Onoda, T. Yamamoto, T. Ohshima, J. Isoya...
quant-ph