[sdlion]

Actually as far as I know, photovoltaic cells are actually "common" diodes. And every diode actually emits light while forward biased, it's like a inherent property of them. Electrons "leap" the electron gap in a NP junction and while "going down" emit a photon. And the reverse is true, a photon of certain wavelength inciding on a NP junction will energize an electron if the wavelength coincides with the electron gap, thus producing a voltage difference.

This is used in more interesting ways on LEDs since their construction exposes their junction to the environment. You can use their small junction capacitance while they're charged and it's variability while being exposed to photons to create "light based touch sensors". You emit the same wavelength light with contiguous LEDs and one of them is "turned off" and time it's discharging rate. Faster? Light is shining over the junction. Lower? there's no matching photons over the junction.

So, I guess yes, is like PV cells but for even wider wavelengths (AFAIK PV cells already try to harvest the most of the sun's infrared light)