1. Haldane FDM, Raghu S. Possible realization of directional optical waveguides in photonic crystals with broken time-reversal symmetry. Phys Rev Lett. 2008;100:013904.
2. Wang Z, Chong YD, Joannopoulos JD, Soljačić M. Reflection-free one-way edge modes in a gyromagnetic photonic crystal. Phys Rev Lett. 2008;100:013905.
3. Wang Z, Chong YD, Joannopoulos JD, Soljačić M. Observation of unidirectional backscattering-immune topological electromagnetic states. Nature (London). 2009;461:772.
4. Yu Z, Veronis G, Wang Z, Fan S. One-way electromagnetic waveguide formed at the interface between a plasmonic metal under a static magnetic field and a photonic crystal. Phys Rev Lett. 2008;100:023902.
5. Takeda H, John S. Compact optical one-way waveguide isolators for photonic-band-gap microchips. Phys Rev A. 2008;78:023804.