  A new mechanism of Bragg reflection is identified, one that, remarkably,
occurs in a uniform medium and relies on resonant tuning of the medium's
parameters. Due to uniformity, reflection ensues over a broad wavelength range,
much like a metal, but it is polarization dependent: one circular state is
reflected, whilst the other is transmitted. Such a medium can thus provide a
broadband, low-loss polarization divider/combiner. Assessment of the required
parameters suggests that manufacturing is within range of current metamaterials
technology. By externally regulating the medium's parameters, a highly
efficient optical modulator is possible with potential applications across
optics, optoelectronics, and photonics.
