Monolithic power monitor and wavelength detector

A monolithic dual detector structure for detecting the optical power and wavelength of light emitted by an optical light source, the structure comprising:

• a first detector structure, the first detector structure having selectively doped areas that provide PIN junctions of a photovoltaic device, the first detector structure further having a sufficiently small optical absorption coefficient, within an optical wavelength range, that limits absorption by the first detector structure to a corresponding small fractional amount of light being emitted by an optical light source;
• a periodic structure on the first detector, the periodic structure being attuned to a particular wavelength within the optical wavelength range such that the periodic structure is substantially transmissive for light of the particular wavelength and variably less transmissive for light of different wavelengths;
• and
• a second detector structure on a second buffer layer on the periodic structure, the second detector structure having selectively doped areas that provide PIN junctions of a photovoltaic device, the second detector structure further having a sufficiently small absorption coefficient, within the optical wavelength range, that limits absorption by the second detector structure to a corresponding small fractional amount of light being emitted by the optical light source;
• wherein the combination of the first detector structure, periodic structure, second buffer layer, and second detector structure is sufficiently thin to be substantially transmissive of light of the particular wavelength propagating therethrough.