finished excercise 2

diff --git a/solid_state_physics/tutorial/1_05s.tex b/solid_state_physics/tutorial/1_05s.tex
index 39d9bdd31b41bce13a2a8869190958fe7492bc03..9c3b7079a6b010d8bb07af956bde370fc9a81b9a 100644 (file)
--- a/solid_state_physics/tutorial/1_05s.tex
+++ b/solid_state_physics/tutorial/1_05s.tex
@@ -78,19 +78,27 @@
  \item
 \end{enumerate}
 
-\section{'Density of state mass' of electrons and holes in silicon}
+\section{'Density of state mass' of holes in silicon}
 
 \begin{enumerate}
  \item $D_v(E)=\frac{1}{2\pi^2}(\frac{2}{\hbar^2})^{3/2}
                (m_{pl}^{3/2}+m_{ph}^{3/2})(E_v-E)^{1/2}$
- \item
+ \item $D_v(E)=\frac{1}{2\pi^2}(\frac{2m_p}{\hbar^2})^{3/2}
+               (E_v-E)^{1/2}$, with
+       $m_p=(m_{vh}^{3/2}+m_{vl}^{3/2})^{2/3}$\\
+       $m_{vh}=0.49 \, m_e$, $m_{vl}=0.16 \, m_e$
+       $\Rightarrow$
+       $m_p=\ldots=0.55 \, m_e$
 \end{enumerate}
 
-\begin{center}
-{\Large\bf
- Merry Christmas\\
- \&\\
- Happy New Year!}
-\end{center}
+Remarks:
+\begin{itemize}
+ \item Operand for calculating the density of states using the
+       standard density of states expression near the band edge.
+ \item No such charge carriers which have the effective mass $m_p$
+       exist in silicon.
+       Concerning transport properties the effective masses have to be
+       treated separately.
+\end{itemize}
 
 \end{document}