A new configuration of photovoltaic systems utilizes solar cells via wave-guides that collect the incoming solar radiation. The waveguide set-up opens new ways to exploit the sun light, among which are light concentration, increased efficiency of longer wave-lengths and enforced spectral selective absorption of the radiation. This spectral splitting into various solar cells along the illumination path aims at a tandem-like solar cell, while avoiding the current matching entanglement.

When light enters a waveguide it propagates along it due to total internal reflection. While grazing surroundings, the evanescent wave penetrates the waveguide surface to a distance of a wavelength magnitude. If the surrounding is a solar cell, the grazing light will be converted into electricity. This leads to decoupling of the charge carriers path from the optical photon path. The longer optical path preserves the effective high optical density, while the work within thin layers reduces the distance that the separated charges need to travel to the current collectors, and thus decreases the recombination of the formed charges.

The system may utilize any solar cell types. The concepts of the above innovation are tested using dye-sensitized solar cells. A single cell is fabricated on a flat waveguide, and characterized by a current-voltage sweep under a one-sun intensity solar simulator. IPCE (Incident Photon to Current Efficiency) spectra of the cell demonstrate the wavelength dependence of the efficiency.