2008 Volume 5 Issue 11 Pages 405-410
We present the new function of tunable hollow waveguides with a variable air core. We show a possibility of wide-angle beam steering from the hollow waveguide and efficient tilt-coupling in narrow air core hollow waveguides. Wide-angle beam steering was demonstrated by calculation and preliminary experiment. In addition, a possibility of an efficient optical coupling with a narrow air core was presented by the tilt-coupling scheme. Input and output coupling losses are 2.5dB and 1dB for 1µm air core, respectively. Wide tunability in sub-wavelength air cores enables us to realize new functions of tunable hollow waveguides and circuits.