  We theoretically study light propagation in guided Bloch surface waves (BSWs)
supported by photonic crystal ridges. We demonstrate that low propagation
losses can be achieved just by a proper design of the multilayer to obtain
photonic band gaps for both light polarizations. We present a design strategy
based on a Fourier analysis that allows one to obtain intrinsic losses as low
as 5 dB/km for a structure operating in the visible spectral range. These
results clarify the limiting factors to light propagation in guided BSWs and
represent a fundamental step towards the development of BSW-based integrated
optical platforms.
