Thermodynamic Basis of the Concept of “Recombination Resistance”

The concept of “recombination resistance” introduced by Shockley and Read [Phys. Rev. 87, 835 (1952)] is discussed within the framework of the thermodynamics of irreversible processes ruled by the principle of the minimum rate of entropy production (MREP). It is shown that the affinities of recombination processes represent “voltages” in a thermodynamic Ohm-like law where the net rates of recombinations represent the “currents” and the Onsager coefficients of the phenomenological laws represent the inverse of the “resistances.” The quantities thus found allow for the definition of “dissipated power” which is to be related to the rate of entropy production of the recombination processes dealt with. The goal of this paper is thus to give a thermodynamical ground to the recombination resistance concept. But, also stressed is the potentiality of the MREP variational method. To this purpose, the simple case of the ideal (Shockley) diode, where diffusion forces are active as well, is considered.