I want to calculate Jsc from EQE and want to match with Light I-V data. Could you please suggests the method?
Dear Arjun
If you have the external quantum efficiency (EQE) of your solar cell then you can calculate the short-circuit current (Jsc) by integrating the (EQE(λ)*AM1.5G(λ)*q*λ/h*c)dλ. Your IV can be obtained: I=Io*(exp(q*V/n*k*T)-1)-Isc (by setting I=0 you can also calculate the Voc=(n*k*T/q)*ln((Isc/Io)+1)).
To do so, you need also spectrum of your light source. Then you need to dot product it with inverse of photon energy at particular wavelength - this will give you a spectral characteristic of your light source in number_of_photons/(time*wavelength)
Then, all you need is to do a dot product of number_of_photons/(time*wavelength) with your EQE data, this will result in number_of_charges/wavelength.
Finally just integrate obtained spectra with respect to wavelength and you will get elemental_charge/second. Divide it by elemental charge, and what you should be left with is Amperes.
There are few tricks here though. First you are supposed to have EQE, and light power spectra in the same decimation - use interpolation to make them equal.
Remember, that when you numerically integrate spectra with 10nm resolution you are multiplying each value by this width (http://en.wikipedia.org/wiki/Riemann_sum)!
Last but not least, if you have not performed all characterization y the same equipment, or you are unsure if it had valid calibration - do not expect overlap better than +-10%.
It is easy to do. You just need to integrate your EQE curve with the standard AM1.5 solar spectrum.
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