  Coherent guiding of atoms in two-colour evanescent light fields of two main
single modes of suspended optical rib waveguides is investigated theoretically.
Special attention is paid to waveguides of widths larger than the wavelength of
light, which provide better lateral stability of the surface traps and
waveguides, and can be used in coherent Bragg beam splitters for matter waves,
based on optical gratings formed by interference of evanescent light waves of
two crossed optical waveguides. A single-mode regime for evanescent-wave
waveguides for atoms is investigated. The general structure and key elements of
all-optical atom chips are discussed.
