X-Git-Url: https://hackdaworld.org/gitweb/?p=lectures%2Flatex.git;a=blobdiff_plain;f=solid_state_physics%2Ftutorial%2F2n_01s.tex;h=38566a87aa5cc8de95f25d76236da60177b2fc1c;hp=b16cf30ade21ea36564ec570713c704e1c2eed6f;hb=94afb95da60b2cdbcd5c328661715eda4416de19;hpb=fdf1f976b879c9b7403c1d76c9906aa850614862 diff --git a/solid_state_physics/tutorial/2n_01s.tex b/solid_state_physics/tutorial/2n_01s.tex index b16cf30..38566a8 100644 --- a/solid_state_physics/tutorial/2n_01s.tex +++ b/solid_state_physics/tutorial/2n_01s.tex @@ -92,7 +92,7 @@ Use: $x=(\epsilon - E_{\text{c}})/k_{\text{B}}T$ $\Rightarrow$ $n=\frac{1}{2\pi^2}(\frac{2m_nk_{\text{B}}T}{\hbar^2})^{3/2} \exp(-\frac{E_{\text{c}}-\mu_{\text{F}}}{k_{\text{B}}T}) - \underbrace{\int_0^{\infty}x^{1/2}e^{-x}dx}_{=1/2\sqrt{\pi}}= + \underbrace{\int_0^{\infty}x^{1/2}e^{-x}dx}_{=\frac{\sqrt{\pi}}{2}}= \underbrace{2(\frac{m_nk_{\text{B}}T}{2\pi\hbar^2})^{3/2}}_{=N_{\text{c}}} \exp(-\frac{E_{\text{c}}-\mu_{\text{F}}}{k_{\text{B}}T})= N_{\text{c}}\exp(-\frac{E_{\text{c}}-\mu_{\text{F}}}{k_{\text{B}}T})$ @@ -101,7 +101,7 @@ $\forall \epsilon$ of states within conduction band: $\mu_{\text{F}}-\epsilon >> k_{\text{B}}T$ $\Rightarrow$ $1-f(\epsilon,T)= - 1-\frac{1}{\exp(\frac{\mu_{\text{F}}-\epsilon}{k_{\text{B}}T})+1}\approx + 1-\frac{1}{\exp(\frac{\epsilon-\mu_{\text{F}}}{k_{\text{B}}T})+1}\approx \exp(\frac{\epsilon-\mu_{\text{F}}}{k_{\text{B}}T})$\\ Parabolic approximation: $D_v(\epsilon)=\frac{1}{2\pi^2}(\frac{2m_p}{\hbar^2})^{3/2}(E_v-\epsilon)^{1/2}$ @@ -110,14 +110,14 @@ $p=\int_{-\infty}^{E_{\text{v}}}D_v(\epsilon)(1-f(\epsilon,T))d\epsilon\approx \frac{1}{2\pi^2}(\frac{2m_p}{\hbar^2})^{3/2} \exp(-\frac{\mu_{\text{F}}}{k_{\text{B}}T}) \int_{-\infty}^{E_{\text{v}}}(E_v-\epsilon)^{1/2} - \exp(-\frac{\epsilon}{k_{\text{B}}T})d\epsilon$\\ + \exp(\frac{\epsilon}{k_{\text{B}}T})d\epsilon$\\ Use: $x=(E_{\text{v}}-\epsilon)/k_{\text{B}}T$ $\Rightarrow\epsilon=E_{\text{v}}-xk_{\text{B}}T$ and - $d\epsilon=-k_{\text{B}}Tdx$\\ + $d\epsilon={\color{red}-}k_{\text{B}}Tdx$\\ $\Rightarrow$ $p=\frac{1}{2\pi^2}(\frac{2m_pk_{\text{B}}T}{\hbar^2})^{3/2} \exp(\frac{E_{\text{v}}-\mu_{\text{F}}}{k_{\text{B}}T}) - \underbrace{\int_0^{\infty}x^{1/2}e^{-x}dx}_{=1/2\sqrt{\pi}}= + \underbrace{\int_{{\color{red}0}}^{{\color{red}\infty}}x^{1/2}e^{-x}dx}_{=\frac{\sqrt{\pi}}{2}}= \underbrace{2(\frac{m_pk_{\text{B}}T}{2\pi\hbar^2})^{3/2}}_{=N_{\text{v}}} \exp(\frac{E_{\text{v}}-\mu_{\text{F}}}{k_{\text{B}}T})= N_{\text{v}}\exp(\frac{E_{\text{v}}-\mu_{\text{F}}}{k_{\text{B}}T})$