August Domel edited To_reach_the_SQ_limit__.md  about 9 years ago

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To reach the SQ limit, electrical and optical properties of the system must meet the ideal conditions, these include:    * infinite mobility : Each absorbed photon generates one single electron-hole pair. A second major limiting factor leading to a degradationof the cell efficiency in relation to the theoretical values pre-dicted by the Shockley and Queisser model is associatedwith series resistance losses, basically caused by the finitevalue of the carrier mobility. However, series resistance effects cansimply be taken into account by introducing a lumped seriesresistance parameterRs, into the initial Shockley andQueisser equation, leading to the well-known implicit equa-tion for the output current of a solar cell (equation is on page 117 of the article). (sqlimitjap2015).  * no non-radiative recombination processes : electrons will not be lost due to phonons.  perfectly reflecting (minority carrier) contacts. The magnitude of these non-radiative recombination losses can be characterized by the internal fluorescence efficiency  * reflections from the front surface (non-ideal ARC): For ideal materials the burden of high open- circuit voltage, and thereby high efficiency, lies with optical design: The solar cell must be designed for optimal light extraction under open-circuit conditions. (Physics required to approach SQ)