Answer:
[tex]n_e = 8.139 *10^6[/tex]
Explanation:
Given that;
The energy gap between the valence band and the conduction band in the widely-used semiconductor gallium arsenide (GaAs) is Δ = 1.424 eV.
So; that implies that:
[tex]\delta \ E = 1.424 \ eV[/tex]
Suppose that we consider a small piece of GaAs with 1020 available electrons, -- This is taking about the numbers of electrons used which is :
[tex]n_i = 10^{20} \ electrons[/tex]
Temperature is given as:
[tex]T = 274.15 \ K[/tex]
Number of electrons can be calculated by using the formula;
[tex]n_e = n_i*e^-^{\frac{\delta E }{2 K_B*T}}[/tex]
[tex]n_e = 10^{20}*e^-^{\frac{1.424}{2*8.617*10^{-5}*274.15}}[/tex]
[tex]n_e = 8.139 *10^6[/tex]