I agree that the square root of the voltage is proportional to the resistance for constant power. This means that the reciprocal of the square root of the current is proportional to the resistance for constant power. These relationships hold whether the resistance is in one resistor or many. For example, 4 resistors of 1 ohm each in series is the same as a single 4 ohm resistor. If the constant power is 1 watt , 2 volts is involved when the resistance is 4 ohms (either 1+1+1+1 ohms or 1 x 4 ohms) and 1 volt is involved when the resistance is 1 ohm.
Tunneling is a colorful word for leakage conductivity through a barrier. There is some leakage through the depletion zone in standard diodes. A diode has asymmetrical conductivity involving amounts of current useful in a circuit through a narrow depletion zone under forward voltage conditions and a useful blockage of current through a wide depletion zone under reverse voltage conditions.
Constant leakage current created by hole / electron pair generation will eventually keep the reverse voltage from going to infinity. Experiment suggests that the open circuit voltage is 0.1 V. If a well designed array operates at a higher voltage, I will drop my provisional hypothesis of an association to IR photon energy. Electromagnetic energy does involve photon energies measured in electron volts where an electron volt is the energy of an electron accelerated by an electromotive force of one volt.
Aloha, Charlie
