<?xml version="1.0" encoding='utf-8'?>
<!DOCTYPE wml PUBLIC "-//WAPFORUM//DTD WML 1.1//EN" "http://www.wapforum.org/DTD/wml_1.1.xml">
<wml>
<card id="card1" title="Exciton - Page 3 - Wikipedia">
<p>
<a accesskey="1" href="page.php?w=Exciton&amp;p=2">1.Previous</a><br />
<a accesskey="3" href="page.php?w=Exciton&amp;p=4">3.Next</a>
</p>
<p>electron state with a positive charge, an analogue in crystal of a <a href="page.php?w=positron">positron</a>. Because of the attractive <a href="page.php?w=Coulomb_force">Coulomb force</a> between the electron and the hole, a bound state is formed, akin to that of the electron and proton in a hydrogen atom or the electron and positron in <a href="page.php?w=positronium">positronium</a>. Excitons are composite bosons since they are formed from two fermions which are the electron and the hole.</p>

<p><big> Occurrences </big></p>
<p>Excitons are often</p><p>
<a accesskey="1" href="page.php?w=Exciton&amp;p=2">1.Previous</a><br />
<a accesskey="3" href="page.php?w=Exciton&amp;p=4">3.Next</a>
</p>

<do type="prev" label="Search">
        <go href="search.wml"/>
</do>

</card>
</wml>
