Patent ID: 8442374

Claim:
An apparatus for guiding light propagation, comprising: a first subwavelength grating layer comprising a first plurality of periodically spaced apart segments of high refractive index material in a grating plane having a selected periodicity between which is disposed low refractive index material; a second subwavelength grating layer comprising a second plurality of periodically spaced apart segments of high refractive index material having a selected periodicity between which is disposed low refractive index material; and a core separating said first and said second subwavelength gratings by a predetermined distance which forms a hollow core through which an incident light beam, having a given wavelength, is propagated along a propagation direction; wherein said core is configured for receiving the incident light beam between the first and second subwavelength gratings and providing lateral confinement in response to glancing reflections from grating segments of said first and second subwavelength grating layers as the incident light beam traverses said core.