From 6d283effbe3004ef67ebae4a627ca228dcd8ad4c Mon Sep 17 00:00:00 2001 From: hackbard Date: Wed, 9 Jan 2008 18:08:29 +0100 Subject: [PATCH] added parts of tutorial and proposed solutions 6 --- solid_state_physics/tutorial/1_06.tex | 71 ++++++++++++++++++++++++++ solid_state_physics/tutorial/1_06s.tex | 70 +++++++++++++++++++++++++ 2 files changed, 141 insertions(+) create mode 100644 solid_state_physics/tutorial/1_06.tex create mode 100644 solid_state_physics/tutorial/1_06s.tex diff --git a/solid_state_physics/tutorial/1_06.tex b/solid_state_physics/tutorial/1_06.tex new file mode 100644 index 0000000..a8b8987 --- /dev/null +++ b/solid_state_physics/tutorial/1_06.tex @@ -0,0 +1,71 @@ +\pdfoutput=0 +\documentclass[a4paper,11pt]{article} +\usepackage[activate]{pdfcprot} +\usepackage{verbatim} +\usepackage{a4} +\usepackage{a4wide} +\usepackage[german]{babel} +\usepackage[latin1]{inputenc} +\usepackage[T1]{fontenc} +\usepackage{amsmath} +\usepackage{ae} +\usepackage{aecompl} +\usepackage[dvips]{graphicx} +\graphicspath{{./img/}} +\usepackage{color} +\usepackage{pstricks} +\usepackage{pst-node} +\usepackage{rotating} + +\setlength{\headheight}{0mm} \setlength{\headsep}{0mm} +\setlength{\topskip}{-10mm} \setlength{\textwidth}{17cm} +\setlength{\oddsidemargin}{-10mm} +\setlength{\evensidemargin}{-10mm} \setlength{\topmargin}{-1cm} +\setlength{\textheight}{26cm} \setlength{\headsep}{0cm} + +\renewcommand{\labelenumi}{(\alph{enumi})} + +\begin{document} + +% header +\begin{center} + {\LARGE {\bf Materials Physics I}\\} + \vspace{8pt} + Prof. B. Stritzker\\ + WS 2007/08\\ + \vspace{8pt} + {\Large\bf Tutorial 6} +\end{center} + +\section{Indirect band gap of silicon} + +Some facts about silicon: +\begin{itemize} + \item Lattice constant: $a=5.43 \cdot 10^{-10} \, m$. + \item Silicon has an indirect band gap. + \begin{itemize} + \item The minimum of the conduction band is located at + $k=0.85 \frac{2 \pi}{a}$. + \item The maximum of the valance band is located at $k=0$. + \item The energy gap is $E_g=1.12 \, eV$. + \end{itemize} +\end{itemize} +\begin{enumerate} + \item Calculate the wavelength of the light necessary to lift an electron from + the valence to the conduction band. + What is the momentum of such a photon? + \item Calculate the phonon momentum necessary for the transition. + Compare the momentum values of phonon and photon. + \item Draw conclusions concerning optical applications. +\end{enumerate} + +\section{\ldots} + +\ldots + +\begin{enumerate} + \item \ldots + \item \ldots +\end{enumerate} + +\end{document} diff --git a/solid_state_physics/tutorial/1_06s.tex b/solid_state_physics/tutorial/1_06s.tex new file mode 100644 index 0000000..f3d6992 --- /dev/null +++ b/solid_state_physics/tutorial/1_06s.tex @@ -0,0 +1,70 @@ +\pdfoutput=0 +\documentclass[a4paper,11pt]{article} +\usepackage[activate]{pdfcprot} +\usepackage{verbatim} +\usepackage{a4} +\usepackage{a4wide} +\usepackage[german]{babel} +\usepackage[latin1]{inputenc} +\usepackage[T1]{fontenc} +\usepackage{amsmath} +\usepackage{ae} +\usepackage{aecompl} +\usepackage[dvips]{graphicx} +\graphicspath{{./img/}} +\usepackage{color} +\usepackage{pstricks} +\usepackage{pst-node} +\usepackage{rotating} + +\setlength{\headheight}{0mm} \setlength{\headsep}{0mm} +\setlength{\topskip}{-10mm} \setlength{\textwidth}{17cm} +\setlength{\oddsidemargin}{-10mm} +\setlength{\evensidemargin}{-10mm} \setlength{\topmargin}{-1cm} +\setlength{\textheight}{26cm} \setlength{\headsep}{0cm} + +\renewcommand{\labelenumi}{(\alph{enumi})} + +\begin{document} + +% header +\begin{center} + {\LARGE {\bf Materials Physics I}\\} + \vspace{8pt} + Prof. B. Stritzker\\ + WS 2007/08\\ + \vspace{8pt} + {\Large\bf Tutorial 6 - proposed solutions} +\end{center} + +\section{Indirect band gap of silicon} + +\begin{enumerate} + \item \begin{itemize} + \item Photon wavelength:\\ + $E_g=\hbar\omega=\hbar\frac{2\pi}{T}=\hbar 2\pi v + \stackrel{c=v\lambda}{=}\hbar 2\pi\frac{c}{\lambda}$ + $\Rightarrow \lambda=\frac{\hbar 2\pi c}{E_g} + =\frac{hc}{E_g}=\ldots=1.11 \, \mu m$ + \item Photon momentum:\\ + $p=\hbar k=\hbar\frac{2\pi}{\lambda}=\frac{h}{\lambda} + =\ldots=5.97 \cdot 10^{-28} \, kg\frac{m}{s}$ + \end{itemize} + \item Phonon momentum necessary for transition:\\ + $p=\hbar \cdot \Delta k=\hbar \cdot 0.85 \, \frac{2\pi}{a} + =\frac{0.85 \, h}{a}=\ldots=1.04 \cdot 10^{-24} \, kg\frac{m}{s}$\\ + $\rightarrow$ Phonon momentum 3 orders of magnitude below + the momentum necessary for transition! + \item +\end{enumerate} + +\section{\ldots} + +\ldots + +\begin{enumerate} + \item \ldots + \item \ldots +\end{enumerate} + +\end{document} -- 2.20.1