Using "h" or "hbar" in the calculation for generation rate

Hi Ahsan,

According to the whitepaper and In this link: https://kb.lumerical.com/en/solar_cells_methodology.html

You mentioned that the denominator for g is hbar instead of h, this would mean that you are off by a factor of pi.
I saw that this is also the case in the script of solar charge generation rate of FDTD Lumerical.
Could you please explain why?
Thanks.

Hi Gede,

The value of “g” is found by dividing the absorbed power at each frequency (wavelength) with the power of a photon at that frequency. This gives us the number of photons absorbed at that frequency. Now the power of a photon at a certain frequency is given by,

E_ph = h * f

This can be re-written as

E_ph = h / (2pi) * (2pi) * f = hbar * (2pif) = hbar * w

This is how we ended up with an “hbar” rather than an “h” in the denominator because we are using the angular frequency (w) rather than frequency (f).