Active control of slow light on a chip with photonic crystal waveguides

Photonic crystals could become the silicon chips of optoelectronics, engineered to control the properties of photons in much the same way that the atomic lattice of a semiconductor controls electrons. Yurii Vlasov and co-workers at IBM's T. J. Watson Research Center have applied photonic crystal technology to ‘slow light’. In this still-new field, pulses of light are drastically slowed and even brought to a halt in various atomic and solid-state systems where material absorption is countered by optical pumping. This has potential in applications ranging from all-optical storage to optical switching. Vlasev et al. demonstrate an over 300-fold reduction of the group velocity of a light pulse on a silicon chip via an ultra-compact photonic integrated circuit utilizing low-loss silicon photonic crystal waveguides. The cover shows a scanning electron micrograph of the experimental setup.