Photon energy lifter
  We propose a time-dependent photonic structure, in which the carrier frequency of an optical pulse is shifted without changing its shape. The efficiency of the device takes advantage of slow group velocities of light attainable in periodic photonic structures. The frequency shifting effect is quantitatively studied by means of Finite Difference Time Domain simulations for realistic systems with optical parameters of conventional silicon technology. 
Zeno Gaburro, Mher Ghulinyan, Francesco Riboli, Lorenzo Pavesi,   Alessio Recati, Iacopo Carusotto